Find if you have eCryptfs
Open a terminal by pressing Ctrl+Alt+T and enter:
df --type=ecryptfs

If you see an output like:
Filesystem                     1K-blocks Used      Available  Use%   Mounted on
/home/.ecryptfs/$USER/.Private 415321024 214784192 179416628   55%   /home/$USER

Then you have your home folder encrypted by eCryptfs.
Background
LUKS encryption and eCryptfs work differently.
First, eCryptfs encrypts the /home/$USER folder, the LUKS works at the partition level.
Second, the encrypted /home/$USER folder is unlocked when the $USER logs in. The LUKS partition encryption would ask for a passphrase every time you boot the computer. Once the /home partition is unlocked you will be able to login to your account with your login password as usual. That is, you will need to use two passwords. If your computer has other users, their "Home" folders will be encrypted as well. Thus all users of the computer must know the LUKS passphrase if they need to turn on the computer and use it in your absence. There is a way to save the passphrase in a file and let LUKS automatically unlock the partition at boot time, but that is not safe.
Third, your computer has only one partition / (plus the swap), as is the case with most Ubuntu installation. There is no easy way to LUKS encrypt this single partition installation of Ubuntu. If you want to keep the single partition setup, you may want to backup your data and reinstall Ubuntu. While installing, select the full disk encryption option.
Finally, BACKUP! BACKUP!! BACKUP!!! The steps described below are very very risky. It is likely that you will lose all the data, or your Ubuntu installation will become unbootable.
Step 1: Create a new partition for /home
Step 1.1: Boot from live CD/USB
Use the try Ubuntu without installing option.
Step 1.2: Identify the disks
Open Gparted. I prefer Gparted because it is visual and let me "see" the drives and partitions.  Click on the top right drop down and see the list of drives. Go through the list and identify the drives you want to work with, by their size and partition structure. You want to identify the / partition in your internal hard drive you want to shrink.

Step 1.3: Shrink
Make sure you have selected the internal disk.
Select the / partition you want to shrink.
Drag the right edge of the partition leftward to resize/move to make room for the new /home partition. Create as much room as you want your new /home partition to be.
Press the "Apply" button in Gparted and wait.
If all goes well go to the next step. If you get an error, stop!

Step 1.4 Create New partition
Right click on the unallocated space you created and select new. You will see the "Create New Partition" window. Make sure the file system says "ext4" and you can keep the rest as is.

Press the "Apply" button in Gparted and wait.
If all goes well go to the next step. If you get an error, stop!
Step 1.5 Reboot computer to internal hard disk
Step 2: Encrypt the new partition
Step 2.1 Find the identifying information about the new partition
Open a terminal by pressing Ctrl+Alt+T and enter:
sudo blkid

You will be prompted for your password. When you type the password nothing will show on the terminal. This is normal.
Copy and paste the output in a text file. Note the UUID as well as the partition name like /dev/nvme0pX, where X is a number for the new partition.
Step 2.2 LUKS encrypt!
sudo cryptsetup -h sha256 -c aes-xts-plain64 -s 512 luksFormat /dev/nvme0pX

You will be prompted to enter a passphrase. This is passphrase will be needed every time you boot the computer to unlock the /home partition. Do not leave it blank.
The next two commands open the encrypted partition and format it to make it ready for data storage.
sudo cryptsetup luksOpen /dev/nvme0pX home
sudo mkfs.ext4 -m 0 /dev/mapper/home

Step 3 Temporarily mount and copy contents of /home
Create a new folder to make it the temporary mount point of the encrypted partition
sudo mkdir /newhome

Mount the encrypted partition to newhome
sudo mount /dev/mapper/home /newhome

Make sure your "Home" folder is accessible. If you have multiple users with encrypted home folders for each of them, make sure the "Home" folders are accessible.
Copy original home to newhome
sudo cp -a /home/* /newhome

Make sure all your files are copied to the newhome and you can see them.
Remove the bits of old encryption system copied in the newhome
sudo rm -rf /newhome/username/Private /newhome/username/.ecryptfs

where username is your username. If you have multiple users in this computer with encrypted "Home" folders, you will have to do this for all users.
Step 4: Setup your newhome as home
Edit the file /etc/crypttab
sudo nano /etc/crypttab

Add the line below making sure the UUID corresponds to /dev/nvme0pX:
home UUID=AAA-BBB-CCC-DDDD-EEEEEEEE none luks,timeout=30

Press Ctrl+X followd by Y and Enter to save and exit nano.
Edit /etc/fstab with nano
sudo nano /etc/fstab

and add the following line:
/dev/mapper/home  /home ext4 nodev,nosuid,noatime        0       2

Press Ctrl+X followd by Y and Enter to save and exit nano.
Do not reboot your computer yet!
Step 5: Remove the old encrypted home and old encryption program
sudo rm -rf /home/*
sudo apt remove ecryptfs-utils libecryptfs1

Note the old /home folder should remain and be empty as this will be used as the mountpoint of the encrypted partition.
Step 6: Reboot
You will be prompted for your home partition passphrase before you can login.
Hope this helps


User creation with mutiple command options

Yes, you can accomplish this with a single command by using the friendlier frontend adduser instead of useradd.

sudo adduser --home /path/to/desired/homedirectory --ingroup specialgroup  newuser


Ubuntu not booting on HP pavilion 17 177-sb with uefi BIOS

Had the same problem, solved going to the command line (press esc at the error message) and ran an update and upgrade of the system, at the restart it worked.
The commands are:

sudo apt-get update
sudo apt-get upgrade
sudo reboot -h now


Figured it out! There is a nice little tutorial on how to do offline rvm installation.
http://groups.google.com/group/rubyversionmanager/browse_thread/thread/1d5dda17c41565bb


VMware Player - Failed to build vmnet. Failed to execute the build command

VMWare player 6 had some issues with the newer kernel versions, and requires patching in order to compile the vmnet modules.  Patches can be found on GitHub.

An easier solution may be to use VMWare player 7


Seems it was connected to my recent upgrade to python 3.5.0. Reverted to 3.4.3, and it works now.


How do I remove the messaging menu for just one user?

Please backup your important files. I tried my suggestion that follows and the result is that it shows the "message" icon, but it doesn't have any sub-options when clicked. I don't know if it affects the system though.

What I would suggest is to change the group of allowed users for this service. I think you can set who can run the command (indicator-messages-service):

$ ls -l /usr/lib/indicator-messages/indicator-messages-service
-rwxr-xr-x 1 root root 65016 2011-09-29 03:02 /usr/lib/indicator-messages/indicator-messages-service

r = read, w = write, x = execute (open folder or run program)
- rwx r-x r-x = r/w/x for owner (currently root), r/x for group "root", r/x for the rest (users not root and not in group root)

Create a group:

sudo addgroup msgok

Add the users for whom you want to allow the message indicator:

sudo adduser myuser msgok

Change "myuser" with your user.
Repeat for other users. Users have to logout/login for changes to take effect.
Change the group of :

sudo chgrp msgok /usr/lib/indicator-messages/indicator-messages-service
sudo chmod 754 /usr/lib/indicator-messages/indicator-messages-service

"754" would basically allow execution of messages service for user root and users in group "msgok". It would also disable the execution of this service to other users, not root nor in group "msgok".

To undo the changes:

sudo chmod 755 /usr/lib/indicator-messages/indicator-messages-service
sudo chown root:root /usr/lib/indicator-messages/indicator-messages-service


You should escape the percent signs with a backslash:

*/1 * * * * mv /media/eagle805/ver1/php/VisitorTracking/data/raw/*.raw /var/www/ver1/php/VisitorTracking/data/raw/. >> /var/www/backups/visitor_tracking_file_move_$(date +\%Y-\%m-\%d).log 2>&1

Reference: man 5 crontab reads near the middle:

  Percent-signs (%) in the  command,
  unless  escaped  with  backslash  (\),  will  be  changed  into newline
  characters, and all data after the first % will be sent to the  command
  as standard input.


Use LaCie Ruged Mini 2TB external drive on Ubuntu 16.04?

Based on reassurance from @heynnema, I went ahead and used the Ubuntu disk utility Disks to delete the "LaCie Setup" partition and add a new Ext4 partition, and things seem to be working fine now.

(At the moment I still have an MBR partition table, not GPT.)


Updating from Lubuntu 18.04 to 20.04 is not recommended as it might break your system. Instead, back up all of your important files, and create a bootable USB or DVD with the Lubuntu 20.04 image on it and install Lubuntu 20.04.


You can upgrade to 18.04 by following this article or just follow my answer. I copied only the necessary parts from the article linked above, so it becomes a little bit easier.
Here we go;

first run these commands, so ubuntu is fully updated. This makes the upgrading to 18.04 easier.

$ sudo apt update
$ sudo apt upgrade
$ sudo apt dist-upgrade
$ sudo apt autoremove

Then we can start the upgrade. By using the following commands;

$ sudo apt install update-manager-core
$ sudo do-release-upgrade -d

You should see the upgrade start by now. For further info take a look at the article.

source: https://linuxconfig.org/how-to-upgrade-to-ubuntu-18-04-lts-bionic-beaver


"Failed to execute child process “python” (No such file or directory)"

You can simply go ahead and create a symlink(softlink) using the following command:
sudo ln -s /usr/bin/python3 /usr/bin/python


MySQL Server not binding to external addresses

My user permissions only allowed my user to connect from a local ip address. I changed it to allow it to login from all IP addresses and that fixed it.


How to get GRUB to be the default bootloader instead of Windows Boot Manager on a UEFI laptop?

This is the longest post I've ever made on a StackExchange site, but this process requires a lot of explanation and attention to detail. It's also somewhat specific to the hardware in question, which requires more explanation.

After a lot of headache, two accidental hard drive reformattings, and lots of frustration with HP's buggy firmware implementation, I finally got Xubuntu and Windows 10 running nicely side-by-side. I've done this with Windows 10, but it should also work with Windows 8.1. Both of these newer operating systems use the new(ish) UEFI firmware system, instead of the traditional BIOS system, which is where most confusions with dual-booting seem to arise. I read lots of things from lots of places with instructions for dual-booting with a BIOS system, that talk about UEFI as if it's just a different kind of BIOS, or an optional layer between BIOS and an OS. UEFI and BIOS are not the same thing; a UEFI is not a BIOS, and a BIOS is not a UEFI. They're completely different. There are some things that need to be done differently when dual-booting with a UEFI system.

Firstly, do not use EasyBCD. I've seen a lot of outdated dual-booting tutorials that recommend EasyBCD, but it is designed to work with traditional BIOS firmware used by Windows 7 and Windows Vista, and it does not work well with newer UEFI firmware (Windows 8, 8.1, or 10). If you have already fiddled with EasyBCD, don't worry- the worst it probably did is make a mess in your EFI boot entries by writing things to the MBR. We'll clean that up in step 4. Speaking of MBR, avoid that like the plague. The Master Boot Record is what's used in traditional BIOS firmware as a list of bootloaders stored in the boot partition (or, if written by Windows, in whichever partition is first) of your hard drive. It's meant to list the operating systems on the hard drive, and tell the firmware which one gets booted first. This does not work well with HP's UEFI firmware. It seems that if there's any MBR modification done, HP's UEFI firmware gets confused and runs back to the Windows Boot Manager, which will completely bypass GRUB.

What you'll need:

A live USB or installation CD with your preferred Ubuntu distribution.
Installation media for your Windows OS. If you're upgrading from Windows 8.1, you can do it without downloading the full 3+ GB .iso for Windows 10- there is a web installer that downloads it as it installs- but, for this method, you need the .iso extracted to a CD or USB drive. It's also a good idea to have it on hand for the future, so you might as well create it now. Since this question is about dual-booting with a UEFI system, you'll need the 64-bit OS.

Make sure you have your Product Key, or you won't be able to upgrade/install.

Optional, but highly recommended: A drive large enough to back up your current Windows files.
Enough space on your hard drive for both operating systems, a boot partition (only 200 MB), and a linux-swap partition (usually the same size as your physical RAM).

Step 1: Make a backup

Back up all of your Windows files and folders that you don't want to lose. As long as you have enough free hard drive space for your new Ubuntu partition, this process should not interfere with Windows files. Should is a risky word, though.

Windows 8.1 has a "make a recovery disk" tool, but I found it useless and non-functional when it came to restoring the backup I made with it. The most straightforward way to preserve the files you don't want to lose is to just open Windows Explorer, and copy them to a backup disk. It takes forever, but it's worth it.

Step 2: Disable Fast Startup, and shut down your computer

You'll need to be logged in as an administrator to do this.

It's very important to disable Fast Startup before installing GRUB, because whether the Ubuntu installer can detect Windows' presence depends on how Windows represents itself in the boot partition. With Fast Startup properly disabled, it should be detected. Detection will be covered in step 4.

Windows 8, 8.1, and 10 use this fancy new thing called Fast Startup, which tells your firmware to load a special bootloader that restores the system to its pre-shutdown state very quickly. Pretty cool, huh? Well, because it changes the EFI system's next-boot option, this feature will have to be disabled while you're installing GRUB. This can be done by doing the following:

Open Control Panel (Windows+X->Control Panel from the desktop in Windows 8+) (apparently Microsoft hates power users, so searching the Start Menu for "Control Panel" is now the fastest way to open it)
Navigate to Power Options
Click "Choose what the power button does"
Click "Change settings that are currently unavailable"
Make sure the box that says "Turn on fast startup (Recommended)" at the bottom is not checked.

More detailed instructions can be found here. You can re-enable Fast Startup after installing GRUB, and it seems not to cause any problems with Ubuntu/GRUB booting. Just make sure it's disabled during the installation.

After you've disabled Fast Startup, shut down your computer. Since Fast Startup is disabled, Windows will do a complete shutdown, and not change the next-boot option in the firmware's EFI manager. (Layman's terms: Windows won't tell your HP system to boot its Fast Startup file when it's next turned on, so it will use the EFI boot manager's list, as it should. GRUB will place itself first on this list.)

Step 3: Set up the partitions with gparted

Before installing Ubuntu, you'll want to use your live CD/USB to make a separate partition for it. That way, it *won't overwrite Windows.

*Make sure you've got a backup. No guarantees- this depends on what Windows has decided to do in your boot partition, and it may also depend on which Ubuntu version/distribution you're using- I haven't used them all.

To make the partitions, you need to boot to your live CD/USB, and open gparted. There are plenty of tutorials on using gparted, and it's pretty easy to figure out, so I'll leave the specifics up to you and the Internet.

You will need 4 partitions:

A boot partition. If you already have Windows installed, you shouldn't need to do anything- it should already be one of the first partitions in your drive. Sometimes Windows also makes another small partition at the beginning of the disk called Recovery. Just leave this alone.

If you're doing a new installation, and you want to start everything from scratch (this will wipe out all of your data), go ahead and delete all of the partitions on your drive, and then make this partition. It should be the first partition; its format should be FAT32; and it should be at least 200 MB in size. If gparted has an option to label it, just call it boot. If there's not label option, don't worry about it. You must, however, set the "boot" and "esp" flags on this partition ; without them, the Ubuntu installer will just ignore it and use a legacy mode install, and Windows (10) will refuse to install altogether with the error "we couldn't create a new partition or locate an existing one". Or not. It seems to depend on how Windows feels that day...

A Windows partition. Again, if you already have Windows installed, this partition should obviously be here, after the boot and Recovery partitions. This is where you want it, but you need to resize it to make room for your Ubuntu partition, and the linux-swap partition. Use gparted's resize/move option to do this. Ubuntu needs at least 5 GB, and the linux-swap partition should be at least half the size of your physical RAM, so Resize the windows partition to make enough room for that. gparted will warn you about potential data loss- shrinking your partition should not destroy or corrupt any data, as long as you don't shrink it down into the space being used.

If installing both operating systems from scratch (again, this will wipe out all of your data), Microsoft says you'll need at least 20 GB for the 64-bit OS, so this partition needs to be at least 20 GB. You'll probably want more than that, though: I just used half of the space after the boot partition for Windows, and half of it for Ubuntu and linux-swap. If you're going from scratch, this partition needs to be formatted as FAT32. When you install Windows, it will format it to NTFS. Do not do this with gparted; Windows' implementation of NTFS is different than gparted's implementation, and Windows may not be able to recognize the partition. In the Windows 10 installer, you should have the option to select which partition to place Windows 10 on. If it's formatted as FAT32, Windows should be able to see it and install itself there. If you can label this partition, label it Windows. That will make it easier for you during the Windows install. Speaking of the Windows installer- don't begin that yet. If you're doing new installations of both Ubuntu and Windows at the same time, instead of upgrading from 8 or 8.1 to 10, it's much easier to install Ubuntu first.

A Linux partition. Like the Windows partition, this can vary in size, but Ubuntu's website recommends at least 5 GB. Again, you'll probably want a lot more than that. If you're upgrading instead of doing a fresh install of both operating systems, you should be able to create this partition in the new "unallocated" space shown in gparted. Make it as big as you like but remember to leave space for a linux-swap partition if you plan on using one. It should be formatted as ext4. ext2 or ext3 should work too, if you prefer those for some reason.

If installing from scratch, make your Ubuntu partition just as described above. Make sure it's formatted as ext4, ext3, or ext2. This will allow Ubuntu to use it, but keep the Windows 10 installer from recognizing it, which should cause it to default to the FAT32 partition you made in step 3, which it can read.

Optional, but recommended: a linux-swap partition. At least half the size of your physical RAM is a good start, but I recommend reading the details. I've got 8 GB of RAM, and a 1TB hard drive, so I just made this partition the same size as my physical RAM.

Step 4: Install Ubuntu first

Whether you're upgrading to Windows 10 from an existing Windows OS, or installing both Windows 10 and an Ubuntu distribution to a new or newly-repartitioned hard drive, it's a lot easier to install Ubuntu first. Ubuntu uses GRUB 2 as its bootloader, which does things the way an EFI bootloader should. Windows 10 uses Windows Boot Manager, which does things... well, the way Windows does them... If you install Windows first, you likely won't be able to boot to Ubuntu without holding down a special key during the boot process to stop the Windows Boot Manager from loading, because Windows Boot Manager doesn't respect GRUB when it's added to its list of bootloaders. So instead, install Ubuntu and GRUB first, then add an entry to GRUB for the Windows Boot Manager.

Step 4.1: Cleaning out old EFI entries (optional)

Please be careful here. Deleting the wrong thing can cause huge problems.

Before installing Ubuntu, we want to make sure that the ghosts of past OS installations aren't going to come back to haunt us in the future. In a UEFI system, operating systems use EFI (extensible firmware interface) files to tell the firmware: "Hey, I exist. This is where you can find me." When a new OS is installed, it adds an entry to the EFI Boot Manager's list, which gives it a unique entry number, and tells the EFI Boot Manager where it's EFI file(s) is/are (Windows registers several different EFI files- one for regular boot, one for a recovery boot, one for Fast Startup- possibly more depending on your firmware and your OS version). The EFI Boot Manager also keeps track of the boot-order: a list of entry numbers that specify what gets booted first. If you've been using EasyBCD; bcdedit; Windows' Boot Repair or Recovery tools; boot-repair in a Linux OS; or even if you've updated Windows or reinstalled it, there's a good chance that your EFI entry list now has some duplicates. At least, that was the case with mine. Having duplicates here can bog down your booting process, as the firmware sifts through the out-of-date or wrong-file entries until it finds a bootloader that works. It can also cause a boot-loop, where bootloader A points the firmware to bootloader B, which points it back to A, and then things start to take a very, very long time...

Anyway, to view your EFI entry list and see what needs to be cleaned, use the efibootmgr package with your live CD/USB. You'll need to install it using sudo apt-get install efibootmgr in a terminal, then run it using sudo efibootmgr. By default, you'll get a list of entries that looks something like this:

When I first used this tool after fiddling with EasyBCD and bcdedit trying to get things to boot in the right order, I had over a hundred entries here, most of them duplicates.

If your boot manager list isn't too cluttered, or if you're not comfortable deciding what can be deleted and what shouldn't be deleted, just skip to step 4.2.

To clean out any entries you don't need, use efibootmgr -b <hex_number> -B, where hex_number is replaced by the number listed with the boot entry. So, to remove the USB Drive (UEFI) entry (numbered Boot2001) in the picture above, I'd use sudo efibootmgr -b 2001 -B. You'll notice that I left some duplicates (all of the 3000+ numbered entries). You can use efibootmgr with different options to view some other attributes of the entries, such as the file paths they point to. Those entries look like duplicates, but they all point to different files used by my HP laptop to update its BIOS. Please be careful what you remove. It can be very difficult or impossible to replace things here. You can also use efibootmgr to change the BootOrder, which it displays. See the man page for more information on this useful tool.

Step 4.2: Installing Ubuntu

After you've cleaned up the EFI Boot Manager entries, if you chose to do so, it's finally time to install Ubuntu. With your live CD/USB loaded, select the install option from the bootloader menu, or launch it from the desktop after logging in. Choose your options on the first page of the installer. The second part will look something like this: (I'm using Xubuntu 14.04, so your installer may vary, but the options should be pretty similar.)

If your installer doesn't detect your Windows installation (like mine), you'll need to select the "Something else" option. From there, you'll get a screen that looks similar to the gparted menu you used to set up your partitions. Simply select the partitions you made, and assign them to the correct mount point by selecting a partition and clicking "Change".

If you're installing both OSes from scratch, do the same thing. Do not use the automatic installation option. You need to make sure Ubuntu gets installed in the ext2/ext3/ext4 partition, not the FAT32 Windows partition.

Step 5: Update or install Windows second

You should have an installation disk for Windows 10. Before you start installing, make sure you have your product key nearby, or you won't be able to install/upgrade. When you boot to the installation CD/USB, the installer is pretty simple. A bit too simple for my comfort- the only button was "Install Windows 10" or something like that, and Windows 8, 8.1, and 10, are infamous for their behind-the-scenes installs, where it simply says "We're getting things ready", and provides no details about what it's actually doing to your system. If you've followed these instructions so far, it should be OK to begin installation regularly.

If you're upgrading from Windows 8 or Windows 8.1, you shouldn't have to do anything special with the installation process. Get through the (very long) installation, and proceed to step 6.
If you're doing a fresh install, the installer will ask you where you want to install Windows 10. Make sure you select the FAT32 partition you made in step 2, and not another partition, or that partition will be wiped and formatted. Because Ubuntu is already installed, Windows 10 should be respectful of the boot partition and not reformat it. Having the rubbish entries cleaned out of the EFI Boot Manager's list will also free up space in the tiny 200 MB boot partition, lessening the chances that Windows will get confused and angry and clear the whole thing for itself.

Step 6: Update and (optionally) customize GRUB

After installing or upgrading to Windows 10, you'll need to reboot to Ubuntu to update GRUB so it includes Windows Boot Manager on its list. Before you do this, disable Fast Startup again. This is done very similarly to how you did it in step 2. The control panel and settings UI are a bit different, but most of the options are still there.

After you've disabled Fast Startup again, reboot your computer.

If Windows boots by default, you will need to hold down the special key for your laptop to get to the system's firmware menu. On my HP Touchsmart, that key is Esc. Other common keys are F12, Delete, F10... Your computer's manual should be able to help you out here. From the firmware menu, boot into GRUB. There should be an option to "select a boot device" or something similar, and Ubuntu or GRUB should be listed there. If it's not listed, look for an option to boot from an EFI file, and browse to /EFI/ubuntu/grubx64.efi or (if you have Secure Boot enabled), EFI/ubuntu/shimx64.efi instead. The actual paths of these files may vary depending on your options, and how your boot partition is set up, but the file names should be the same. Selecting one of these .efi files should boot to GRUB, where you can then boot to your Ubuntu distribution. Once you've logged in, open a terminal and type sudo update-grub. This will run the os-prober script that GRUB uses to compile grub.cfg, which tells grub's EFI file which entries to include, what colors to use, etc. The os-prober script should identify Windows Boot Manager, and automatically add it to the list.

Optionally, you can install Grub Customizer to change the order of menu entries and change the behavior and the color and background of the GRUB menu. You can install this from a terminal using sudo apt-get install grub-customizer, and then run sudo grub-customizer.

When using GRUB on a UEFI system shared with a Windows OS, DO NOT install to MBR. Some tutorials list it as a crucial step to use Grub Customizer's "Install to MBR" option under the File menu. You should not do this on most UEFI systems. The MBR (Master Boot Record) is designed for BIOS firmwares, and is still used by the Windows Boot Loader to some extent. Adding GRUB to the MBR, when it's already in the EFI entry list, can cause lots of hairballs.
If you need to make sure that GRUB is the first entry in the boot-order list (i.e. if Windows is always booting, even though you did everything right), use efibootmgr (see step 4.1) to view/edit the EFI Manager's boot order.

Notes

I haven't mentioned Secure Boot at all, because it should normally not affect Ubuntu's installation. Many dual-booting tutorials talk about disabling it, but that's usually not necessary with a current 64-bit installer. However, each PC is different, and Secure Boot is fairly new (2012), so different firmwares may implement things differently. For example, the version of my HP firmware includes a "legacy boot" option, which disables Secure Boot and treats installed OSes as though it were BIOS firmware: some people recommend enabling this for installing for dual-boot. Installing Ubuntu in legacy boot mode on my system prevented GRUB from adding itself to the EFI entry list, so all it could do was add itself to the MBR, which Windows Boot Manager had full control of. Windows Boot Manager took a lot of tweaking to even display the list of entries, and after all that, it would only boot the Windows entries, making GRUB unusable without manually selecting its EFI file every time I powered on.

See here for more information on Ubuntu and Secure Boot and Legacy Boot, and information about the difference between UEFI and BIOS installations in general.


How to install Zend Framework 2 on ubuntu?

You could download directly the lib by pulling the git repository:

https://github.com/zendframework/zf2

PS: Don't download from the master branch, choose a tag.

Or, if you know how to use composer, a PHP package manager, thats an option too.

You could learn by reading the guides in the official web site:
http://framework.zend.com/learn/

More download options:
http://framework.zend.com/downloads

A personal note: Zend is a complex framework if it is yours first experience using a MVC framework. I recommend you to try Cake or Laravel(Ruby on Rails style) if it is your case.


identify: error while loading shared libraries: libgvc.so.5: cannot open shared object file: No such file or directory

You have self-compiled identify in /usr/local/bin/. Possibly from the time of 12.04 LTS release or similar.

You should remove it with

sudo rm /usr/local/bin/identify

and then you will be able to use normal one from the repository.


Customize nemo keyboard shortcuts in Ubuntu 13.04

Anand Sharma answer (after I edited his question):

  The "accels" file for Nemo when installed with the method linked to
  above is located at: ~/.gnome2/accels/nemo. The two
  files, ~/.config/nautilus/accels and ~/.gnome2/accels/nemo are very close to
  the same.

  The reason why I desperately wanted to find how to edit
  keyboard-shortcuts was cause I HATE the default for focusing on the
  location-bar which is Ctrl + L. Practically
  every other application you can think of (e.g. Windows Explorer, Internet Explorer, Chrome, Firefox... list goes on) that has an
  "address bar" places focus there using the Alt+D
  combination.

  Editing the following line in either of the "accel" files did the
  trick for me (make sure you remove the semi-colon, too):

  From:

; (gtk_accel_path "<Actions>/ShellActions/Edit Location" "<Primary>L")

  To:

(gtk_accel_path "<Actions>/ShellActions/Edit Location" "<Alt>d")


deberias reinstalar, que especificaciones tiene tu compu ? D: la verdad nunca me ha pasado eso pero debe de ser algo que esta mal instalado , ammm si estas conectado a internet por cable prueba metiendo las actualizaciones por linea de comandos aver si actualizandolo lo soluciona siempre me ha funcionado eso

sudo apt-get update && sudo apt-get upgrade


Maybe you can try to disable the KMS of Radeon... See http://tomlowshang.blogspot.com/2010/04/disabling-radeon-kms.html and the comment

It works on my PC, HP ProBook 4421s, my graphical driver:

    01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Robson CE [AMD Radeon HD 6300 Series]


Print a web page to PDF and retain links

Assuming you're using Firefox, this is a long-standing request (12 years and counting).
There are some alternatives listed in this Super User post, some of them being:

Use some extension to Firefox
I didn't feel like adding random extensions for this, so I haven't tested any.

Use wkhtmltopdf
I got some odd font-rendering issues (top half of monospace fonts were cut off). Not sure why. Otherwise the PDF looked good. One user suggests using pandoc via LaTeX conversion.
Probably won't work for authenticated pages.

Use Chrome/Chromium.
This is what I ended up doing. It's automateable:
google-chrome-stable --headless --disable-gpu --run-all-compositor-stages-before-draw --print-to-pdf=some-file.pdf proto://some-uri

You might be able to rely on saved cookies with Chrome to avoid the login issue.


Icon too large and blurry in system tray

I've had the same problem with Forticlient VPN and found a workaround for it:
Find the image in e.g. the installation directory of your application and resize it to a smaller size using e.g. nomacs.
In my case, I've resized the original icon size of 42x42 to 16x16, which was a bit too small, seems like 20x20 could be fine.
It IS a workaround, but at least it prevents overlapping of the top panel over fullscreen window controls.


terminator not starting when default python is python3.4 but works if it is python2.7

You can simply fix it by editing /usr/bin/terminator shebang path back to python2, see https://bugs.launchpad.net/ubuntu/+source/terminator/+bug/1621156


use "tee" command to append asterisk debug information to file

The "weird characters" in your sample appear to fall into two categories:

ANSI color sequences
^M sequences, representing carriage returns (suggesting the application uses DOS-style CRLF line endings).

According to Asterisk options - Connecting to a running Asterisk there is a -n command line option to suppress the former:

  -n:Disable ANSI colour support

There doesn't appear to be an option to specify Unix-style LF line endings, however you should be able to pipe the output through any one of the many "DOS to Unix" commands such as tr -d '\r' i.e.

asterisk -rnvvv | tr -d '\r' | tee temp-log-asterisk.txt

Note that this will remove colors from the on-screen output as well.


Folder browser: Copy to restricted locations?

To do exactly as you want, gksudo nautilus will work.

This prompts a follow-up question - what are you trying to do?


First, it was Boot Repair, not Ubuntu's installer, that replaced the Windows boot loader with another copy of GRUB. Boot Repair does this because it's the only available workaround for some buggy BIOSes that will launch the Windows boot loader but not a Linux boot loader; but IMHO, Boot Repair is far too quick to resort to this solution, which is an inelegant (albeit occasionally necessary) hack. IIRC, there's an option in Boot Repair to undo this change. If you can't find it, you can do the same thing manually by renaming files. The Microsoft boot loader should be EFI/Microsoft/Boot/bootmgfw.efi on the ESP (which is mounted at /boot/efi in Linux; see below). In your case, that file will hold a copy of GRUB, and the real Microsoft boot loader will be renamed with another extension or with a few new leading characters -- the Boot Repair developers seem to have changed the names they use at least once. Note that if you rename your boot programs correctly, it's conceivable that your computer will begin booting Windows directly when you power it on, giving you no option to boot Linux. If this happens, you may be able to find Linux in your firmware's own boot manager (usually launched by hitting a function key at boot time); and you can probably restore GRUB to be the default by using the efibootmgr program in Linux. See my Web page on EFI boot loader installation for details.

The /boot/efi directory is empty because it's a mount point for the ESP, and as you've reported, the system has been unable to mount it. This is most likely because of filesystem damage, although it could be that your /etc/fstab entry for /boot/efi has an error. Try this:

Type sudo parted /dev/sda print. This should produce a list of partitions on your disk. The ESP is normally a FAT partition with the "boot flag" set, in parted's nomenclature. Identify this partition and note its number. If you can't find a FAT partition, that could be because of very serious damage to the ESP -- but this seems unlikely, given that you can boot.
Type sudo mount /dev/sda1 /boot/efi, changing 1 to whatever number you identified in the first step. If there's an error message, take note of it; it may be a clue about what's wrong.
If you were unable to mount the ESP, type sudo dosfsck /dev/sda1, again changing 1 to the correct partition number. This will run Linux's FAT filesystem check utility on the partition, which with any luck will fix the problem. You can then try manually mounting the partition again.
If you were able to mount the ESP without running dosfsck, look for its entry in /etc/fstab and fix any problems with it. I know this description is vague, but it's hard to know what might be wrong without seeing the entry. Post it here if you need further advice.

You mentioned Windows 7, but be aware that Windows 8 doesn't use a normal shutdown by default. Instead, it uses a "fast startup" feature that's more like a suspend-to-disk operation. One consequence of this is that filesystems are left in an inconsistent state. I've heard of this feature causing problems with the ESP on some computers, which is why I mention it. When dual-booting with Windows 8, you should disable the "fast startup" feature, as described here. Even in Windows 7, you might see something similar if you used a suspend-to-disk feature or otherwise did not shut down cleanly.


Google chrome does really follow the old fix. You should use this command to put them in right.

gsettings set org.gnome.desktop.wm.preferences button-layout ':minimize,maximize,close'

This worked for me. You can also do the same using dconf-editor.


How to check if gpg key already exist with bash then skip downloading/adding?

How about something like:

TEST=$(apt-key list 2> /dev/null | grep my_app_name)
if [[ ! $TEST ]]; then
    echo "Missing - need to run --fetch-keys or --recv-keys"
fi

I piped stderr into the null device ( 2> /dev/null ) to hide the warning you get for using apt-key list in a script.

Try running "sudo apt-key list" on its own so you can see what the output looks like, in case you want to change the "grep" to be more selective.


Uploading code to arduino gives me the error: "avrdude: ser_open(): can't open device "/dev/ttyACM0": Permission denied"

I had a similar issue when I tried to upload a sketch to Arduino. The issue was connected to the lack of permissions to read/write to the serial port. I was able to fix by using the following command:

To confirm the port exists enter the following from the root directory.

ls /dev/ttyACM0

To set read/write permissions, enter the following

sudo chmod a+rw /dev/ttyACM0


Since your friend is connecting via SSH:

Blocking the IP address might be a bad idea, i assume that you have some DHCP server running in your LAN -> the attacker's IP address will change eventually.

You could also block him based on the MAC address, that will however only work when he is connecting from the same sub-net.

I recommend you to change the password, since that is the root of the problem.

As an alternative you could disallow your own user to login via ssh and create a new user that you use for connecting to your computer. Of course you must not give that users's password to that friend of yours, that's self explaining. (Once connected with the new user you can use the su command to switch into your original user)

There are of course a lot of other solutions for your problem, but i really suggest you just to change the password.

Update

To disable SSH access edit sshd_config (vim /etc/ssh/sshd_config) and
search for DenyUsers. If there is no such entry add it in a new line, so will end up with the following: DenyUsers <the-username-to-block>

Now restart the sshd daemon : sudo /etc/init.d/ssh restart

Now add a new user with adduser <some-new-name>. Once connected with the new user use su <your original username> to switch into your original user's context.


Ubuntu 12.10(32bit) takes very long to install - horribly slow it's a compliment

It is possible that it is downloading files runtime while installing. If same is the case and your internet connection is slow, you may have faced the issue.


Check if IP is static or dynamic programmatically

You can put scripts in /etc/network/if-up.d to be executed when an interface is activated (either by ifup or by Network Manager). These scripts receive information about the interface, including the environment variable $METHOD set to static or dhcp. This is documented in the interfaces(5) man page.

#!/bin/sh
## This is /etc/network/if-up.d/zzzz_alex_notify_myserver
case $LOGICAL in
  eth0)
    case $METHOD in
      dhcp) <notify server that it's on DHCP>;;
      static) <notify server that it's on a static IP configuration>;;
    esac;;
esac


New hardware (Intel i3-8300, old = N3150) with same OS (LTS 16.04)

In terms of hardware, you'll be fine.  Linux detects all hardware on every startup, so as long as you have a standard Ubuntu generic kernel and hardware it supports, hardware changes won't be an issue.

However, as you note, different network hardware may be assigned different device names in Ubuntu 16.x or later, which may require you to know how to detect the network device names to do certain things.  It's very likely that Ubuntu will just start up and work, but if (for instance) you have a Conky that tracks network connectivity or performance, its config will need to be edited to reflect the new network device names.

As noted in comments, if you have or need proprietary graphics drivers, Ubuntu may start up with free/open drivers for the new machine's graphics hardware, or with a fallback video driver -- generally, except for specific issues, you'll likely still have a GUI if you had one before the rebuild, but it may be low resolution and slow until you install or select the correct compatible driver.


Actually the package you may need care of is ntpdate. It have 2 hook to run after:

network interface is up: /etc/network/if-up.d/ntpdate
dhcp client exit: /etc/dhcp/dhclient-exit-hooks.d/ntpdate

So check system log, may be you have problem with network

~$ grep ntp /var/log/syslog
Jul  8 10:04:57 BlueSkies ntpdate[3634]: name server cannot be used: Temporary failure in name resolution (-3)
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: query[A] ntp.ubuntu.com from 127.0.0.1
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: forwarded ntp.ubuntu.com to 192.168.1.1
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: query[AAAA] ntp.ubuntu.com from 127.0.0.1
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: forwarded ntp.ubuntu.com to 192.168.1.1
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 91.189.94.4
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 91.189.89.199
Jul  8 10:05:02 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 2001:67c:1560:8003::c7
Jul  8 10:05:08 BlueSkies ntpdate[3908]: adjust time server 91.189.89.199 offset 0.069675 sec
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: query[A] ntp.ubuntu.com from 127.0.0.1
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: forwarded ntp.ubuntu.com to 192.168.1.1
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: query[AAAA] ntp.ubuntu.com from 127.0.0.1
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: forwarded ntp.ubuntu.com to 192.168.1.1
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 91.189.94.4
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 91.189.89.199
Jul  8 10:05:20 BlueSkies dnsmasq[3777]: reply ntp.ubuntu.com is 2001:67c:1560:8003::c7
Jul  8 10:05:21 BlueSkies systemd-timesyncd[800]: Synchronized to time server 91.189.94.4:123 (ntp.ubuntu.com).

Also I would recommend changing the default ntp server name to IP which removes another layer of failure (DNS resolving). See /etc/default/ntpdate

The above log is from a Ubuntu 16.04 machine, that's why there was a 3rd sync request from a systemd unit systemd-timesyncd.


Arabic Saudi Arabia not available in Regional Formats list

If you have Arabic language added to the list of system languages

You will have the option to choose Arabic SA from the regional format Tab as seen below

Try this:

Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the commands below.

sudo apt-get update && sudo apt-get upgrade


First off, i would check my BIOS to see if you have Safeboot enabled.
I think you would not get  this warning if this is turned off.

Press F1 at boot, enter BIOS and disable safeboot.

Run the installation again.


The folders under /usr/share are used for this purpose.  Though most are application-specific, you'll find directories for things like fonts, man-pages, documentation (for packages), dictionaries, icons, sounds and backgrounds.  The drawback is that while somethings are collected in one directory (like /usr/share/icons and /usr/share/fonts), other things are spread over many...  E.g. you'll find desktop-backgrounds spread between several /usr/share/* -folders, as each WindowManager/DesktopEnviroment install their own in their own directories under /usr/share (e.g. a background-folder somewhere under/usr/share/kde for KDE).


You need to install the wifi driver. Go to additional drivers to download and apply a driver on your system. If you can't find additional drivers then go to software sources/softwares and updates, go to the last tab Additional Drivers. From there you can enable your Wifi driver.


Try installing libasound2 and libasound2-plugins.

sudo aptitude install libasound2 libasound2-plugins

--Edit--
Installing flashplugin-nonfree-extrasound may solve this problem as well.

sudo aptitude install flashplugin-nonfree-extrasound


ubuntu18.04 boot failed because of not exit 0 in /etc/rc.local file

The /etc/rc.local files on Ubuntu and Debian systems are used to execute commands at system startup.

So let's Create the /etc/rc.local file with your fav text editor.

vim /etc/rc.local

copy and paste the below.

#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.

exit 0

save and exit

Now make it executable.

chmod +x /etc/rc.local

That's it. You can now use this file to execute commands at system boot.

Just paste your commands above the line that says exit 0


How to see available wireless networks on 12.10?

It might be the nm-applet hanging. I've had problems with it listing the available networks right after login. The solution is to kill and restart it.

sudo killall nm-applet && nm-applet &


Login with SSH authorized key with changed SSH port

You can specify a non-default port on the ssh client command line using the -p option. From man ssh:

 -p port
         Port to connect to on the remote host.  This can be specified on
         a per-host basis in the configuration file.

You may wish to put both the port number and the identity file location for the host in a ~/.ssh/config file so that they don't need to be specified every time on the command line.

Ex.

Host myremotehost
  Hostname      555.555.555.555
  User          user
  Port          20002
  IdentityFile  /Users/myuser/.ssh/vpsssh

Then you will be able to use:

ssh myremotehost


Trying to get Sims 4 to work on Ubuntu 16.04

Try disabling Origin In Game under Application Settings.


eclipse: class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0

I have encounter the same problem earlier when I downloaded JDK 11 and tried to mess around with java 11, and I tried other comments too but no success. However, go to Window -> installed JREs and install most recent version of jdk solves my problem.
My guess is that the newer version of java needs to be uninstalled so that the earlier version of java can be used, as I have read from this How do i find out the JDK version Eclipse is using?, combines both answers it seemed like:

Actually Eclipse has its own compiler. You can develop java apps using only the JRE and Eclipse
You can still check/set which JDK version you want to compile to. If you go to Window->Preferences, then click "Java" from the menu on the left and then "Compiler". The first setting allows you to see which JDK version is being complied with.
I know this doesn't directly answer your question since JDK isn't actually compiling it, but hopefully it helps!

I just found another way that can solve the problem.
Here's where to add compatibility for it:

Add jdk here:

And the problem solved.


XPS 15 9560 use HDMI port whilst bypassing GPU?

You can disable your GTX1050 with Bumblebee.

https://wiki.ubuntu.com/Bumblebee

You'll get better battery life and the HDMI + USB C HDMI is working for me on ArchLinux

https://wiki.archlinux.org/index.php/Dell_XPS_15_9560#Graphics

-Source I have an XPS with running Windows and Linux


Why resting Unity Interface? Почему сбрасывается Unity окружение?

Indeed, I think you have a bug. You should report it: type Alt+F2 to be able to launch a command, and then type apport-bug nautilus and press Enter.
Wait some time, and then Click on "Send report". Thank you for your help!


Lubuntu: Attach Wifi Driver to fix "network UNCLAIMED"

You could certainly download the driver to a USB drive and transfer it to the Ubuntu computer. Unfortunately, the driver has several dependencies; that is, other packages that are required to compile the driver. Those dependencies themselves have dependencies! This is known in Linux-land as dependency he**.

Here is a post that describes the USB process, although it is for a different device and driver combination. The exact driver is not appropriate to your device. Installing the driver for TP-LINK TL-WN727N on Ubuntu 14.04 Of interest to you and others is the part that says, in relation to the USB method, "Here is how to do it in about five days...maybe."

In contrast, the ethernet and terminal method takes five minutes! I asked for your kernel version, which turned out to be 5.3.0-xx, because the methods posted here on Ask Ubuntu for older kernel versions don't work with 5.3.0-xx.

With a working internet connection, open a teminal and do:

sudo apt update
sudo apt install git build-essential
git clone -b extended https://github.com/lwfinger/rtlwifi_new.git
cd rtlwifi_new
make
sudo make install
sudo modprobe rtl8723de

Your wireless should now be working.

You have compiled the driver for your current running kernel only. When Update Manager installs a later one, also known as linux-image, after the required reboot, re-compile:

cd ~/rtlwifi_new
make clean
git pull
make
sudo make install
sudo modprobe rtl8723de


Mounting external HDD via windows/Virtualbox

Assuming you have installed VirtualBox with extensions, after plugging in your USB HDD, you should be able to open the machine settings, open the USB page, and add the HDD drive as a device accessible from the VM. Start the VM and it should see the USB HDD as if it were a USB drive.


How to properly configure Virt-Manager (QEMU/KVM) with Windows guest

The easiest way to get all of the required drivers into a Windows guest is to use the SPICE Guest Tools Windows installer. Downloading spice-guest-tools-latest.exe should always give you the latest version.

This package includes the Windows QXL/WDDM display driver along with all of the virtio drivers for virtual hardware provided by KVM, and installs all of them at once.

Note that KVM does not provide file sharing to Windows guests. You still need to set up Samba yourself for that.


the driver for the L360 can be downloaded from here; http://download.ebz.epson.net/dsc/du/02/DriverDownloadInfo.do?LG2=EN&CN2=&DSCMI=34541&DSCCHK=141ba614c212ead0099d27f8dc8f2bc35faf7781

if you have 64bit Ubuntu, you need epson-inkjet-printer-201401w_1.0.0-1lsb3.2_amd64.deb

As you click to download, your system may offer to "open" the package, this should mean gdebi installer will install the package; thus install the drivers; if you save to your Downloads folder instead, you can install from there.

Best delete any existing L360 icon in your PRINTERS folder before installing the above; rationale being delete what you say is not working


Lenovo Z360 sometimes doesn't suspend, freezing up completely

This is a known bug with suspend, and unfortunately there seems to be no fix for it as yet (as far as I know). I'll try to find a link if I can to one of the bug reports (I remember seeing it reported more than once).

In my experience, it tends to happen under the condition that the system is hot, so I'm not sure if that is related. It also happens often the first time I suspend after a kernel update, then ceases to occur again until either:

The system is piping hot.
I've done a kernel/driver update.

My suggestion, don't suspend if it's really hot, rather allow it to cool first (keeping a high intensity application running on suspend is a bad idea, even on windows, and generally is the cause of the heat problem), and restart twice after a kernel update (somehow that fixes it for me, not sure why).


video thumbnails not showing in 20.10, HattinGokbori87 solution doesnt work

The answer is here https://askubuntu.com/a/1080512/740291 thanks to Hatsune which is slightly different to HattinGokbori87 solution...
sudo apt install ffmpegthumbnailer

Then I restarted the computer but I still could not see the video's thumbnails in the file manager, so I tried to install another package like this:
(edit: this is the important part to get it working for Ubuntu 20.10)
sudo apt install gstreamer1.0-libav

Then cleaned up the directory like this:
rm -r ~/.cache/thumbnails/fail

Re-opened the Ubuntu file manager, it works!
Update: For Ubuntu 20.04 this method still applies (I just upgraded my computer operating system from Ubuntu 19.10 to Ubuntu 20.04).
edit: This works for 20.10 also.


WARNING: The OpenGL rendering context obtained on X display

I GUESS, it is a problem with the nvidia driver. Reading the link you posted, on how you installed bumblebee, I see that you installed the nvidia driver manually. My suggestion is to change runlevel by pressing:

STRG + ALT + f6

then stop the window-manager

sudo stop lightdm

and uninstall the nvidia driver

sudo apt-get remove --purge nvidia

Since you have already added the swat-x-repos, you should then be able after restarting to install nvidia again from the repositories following step 1 and 2 again and then typing

sudo apt-get install nvidia-331 bumblebee-nvidia

Hope that helps.


How to make gnome always run a script, not ask if it should be displayed?

Launch nautilus and go to Preferences->Behavior, you will find your choices.

Equivalentely, launch gconf-editor and set the value of the key

  /apps/nautilus/preferences/executable_text_activation

to launch.

Alternatively, create a launcher pointing to your script, and make it executable. This option is better, because involve the single script and not all executable text files.


The problem is not caused by a bad setup at the client but by a bad setup at the server. The server is only providing the leaf certificate and not the chain certificates which are needed to create the trust path to the local root CA - see SSL Certificate framework 101: How does the browser actually verify the validity of a given server certificate? for more (the post is about browsers but it is the same for FTP clients).

The wrong setup can be determined with openssl s_client:

$ openssl s_client -connect lautre.net:21 -starttls ftp
...
Certificate chain
 0 s:/CN=lautre.net
   i:/C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3
...
    Verify return code: 21 (unable to verify the first certificate)

As can be seen here, the server sends only the leaf certificate. A proper setup would instead look like this:

$ openssl s_client -connect some-other-server
...
Certificate chain
 0 s:/CN=some-other-server
   i:/C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3
 1 s:/C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3
   i:/O=Digital Signature Trust Co./CN=DST Root CA X3
 ...
    Verify return code: 0 (ok)

Here the expected chain certificate for Let's Encrypt Authority X3 is provided so that the trust chain can be created against the local root CA DST Root CA X3.


gcj is provided by gcj-jdk, gcj-4.8-jdk, gcj-4.9-jdk, gcj-5-jdk and   gcc-snapshot in Ubuntu 16.04. Before you try to install any of these packages, run the following command to show what version(s) of gcc you have installed on your system.

apt-cache policy gcc gcc-4.8 gcc-4.9 gcc-5

If you have only gcc-4.8 installed on your system, it's obvious that you don't need to install gcj-4.9-jdk or gcj-5-jdk.


Ubuntu on Windows: Configuring terminal colors

I tried this out today because I was interested, and found it pretty simple to change things.  Obviously, things might have been different back when you tried:

Right click title bar of the 'Ubuntu' application
Click Properties
Click the Colors Tab

Once here, you see the 16 standard colors (8 + 8 bold) from old terminal days.  You may adjust any of these.

Some Notes from me messing around with it:

This dialog is very wonky.
It's used both to change the color definitions and the selected default for the 4 radio choices shown.  Basically, make sure you move the selection back after altering colors
There is a bug when you first come into the dialog, or switch the radio button, the values in the RGB entries may not represent what you are actually changing, best to explicitly select your color slot, then change it.

But, that's not all...

I have a color script that I've assembled over the years that you can put in your path on windows and execute it from Ubuntu on Windows as /bin/bash colors.  I ran this and here are the results:

First, it shows that changes to the terminal definition of the 16 colors are working...

But it also shows that the terminal is capable of displaying the full 256 color palette that modern terminals can do.  So, you have many options for altering the appearance of your terminal.  You can change the base 16 color definitions, or even better (maybe) you can start referencing the full spectrum in your scripts/prompts, etc.

Search the web for 'bash prompt 256 colors' to get you started.  Many terminal applications support 256 colors if you look for them.

References:

https://unix.stackexchange.com/questions/93268/bash-ps1-256-colors-with-bold
https://unix.stackexchange.com/questions/25319/256-colour-prompt-in-zsh
https://gist.github.com/ricardochimal/293517
https://gist.github.com/dpb1/6820bc97ddf81c72541d6fa7954e56a3


You should be able to use getline to read from the special filename /dev/stdin:

#!/usr/bin/awk -f

BEGIN {
  printf "Enter the type of school (AFA, CEE, CFA, EASD): "
  getline center < "/dev/stdin"
}

{
  print center, $0
}


I have Chromium Queued for Installation and nothing is happening?

Okay thanks all! I could rate those answers from "very helpful and friendly" to "what are you doing here?" For a complete newb that has used PC's since the command prompt days I know nothing but all Window's OS. So if this is a forum that is above these types of questions possibly another forum for the unenlightened could be suggested?
I managed to pull my enlightened neighbor over here who has been using Linux family for years. He took note the reason it was not downloading was I was only using the "kick the tires" option and had to install it to get downloads. Once done the download happened. Oh to answer . . .
I have this very old 2005 era Toshiba Notebook Laptop. He helped me install Ubuntu Mate. 18.04.4 LTS I believe I saw somewhere Bionic Beaver? But not sure.
Things that had not worked on 2 factory resets with Windows disk, the wireless adapter to point, are working with this OS. It's a PC dedicated to only one thing and that is a way to remotely work on my Google Docs away from the main PC.
Before I scram with my tail between my legs is there any suggestion for the fastest browser for this older machine. I have Chromium, FF and Vivaldi installed and trying to compare. I only need a lightweight that will insure I can run Google Docs and that's about all. I'll Google if Ubuntu should be defragged now and then. I won't ask that here. :-\
Thanks to all of you. I've joked but I'll move if someone tells me where better to ask these questions.
G'day to all!  jack  ":-}


simple-scan failed to scan, unable to start scan with HP color laser jet pro MFP M477fdw

I got it working. I ran sudo apt install hplip-gui then hp-setup. It couldn't discover the scanner so I had to enter its hostname. I chose to not add another print queue (it was already there) and not add a fax queue.
simple-scan ("Document Scanner") now shows three options for scanners. One works. The one that works is named "HP HP_Color_LaserJet_MFP_M477fdw".
I think the important thing hp-setup did was to download a plugin. I had to enter my credentials so it could install the plugin. Then I just skipped printer & fax setup and closed the hp-setup GUI, then ran simple-scan.
I don't see a HP icon in my system tray even after doing this.


How do I type a backtick in RubyMine with a Swedish keyboard layout?

I couldn't reproduce the problem in RubyMine on natty.

If you still suffer from the problem, try the following work-around: change the system keyboard layout from Keyboard Preferences > Layouts > Add and pick Country: Sweden and Variants: Sweden Eliminate dead keys. That will give you the backtick by just pressing S-Backtick. If you need to change between the regular and eliminate dead keys layout variants, keep both available in layouts and set a convenient hot key to switch (in the Layouts tab click on Options... and then Key(s) to change layout).


After updating from 18.04 to 20.04 HP OfficeJet 8720 produces no output

I unplugged the 8720 and plugged it back in. It then printed.


Cannot boot to Windows 10 after failed installation of Ubuntu!

Try this link: http://www.howtogeek.com/howto/32523/how-to-manually-repair-windows-7-boot-loader-problems/

[EDIT]
This link is for Windows 10: http://www.thewindowsclub.com/repair-master-boot-record-mbr-windows

You will need Windows bootable drive like flash drive or DVD. Eventhough its says its for Windows 7 it must also work for others I suppose. However I have not tried it.

Boot from windows DVD/Flash drive
Select repair computer
Choose command prompt
Enter the following commands:

bootrec /fixmbr


Does the Ubuntu installer create a hybrid MBR partition table on EFI systems?

Although a year later, I'd like to share my findings about Ubuntu and disk partitioning. I have been playing with Linux Mint 18 (that just came out). It is based on Ubuntu 16.04. I installed it by letting it use all disk space automatically. Please, note that I am doing it on an iMac 2009 which has some soft of EFI bios. After the installation I ran gdisk -l /dev/sda and it said:

  MBR: hybrid BSD: not present APM: not present GPT:
  present

On the other hand, as an experiment, I tried manually partitioning the disk by creating protective MBR and then installing. The installation went just fine and it boots with no problems. So, it seems that Hybrid MBR is not mandatory.

I read this post about the dangers of Hybrid MBR: http://www.rodsbooks.com/gdisk/hybrid.html I have no idea why the installer creates MBR: hybrid when it should be avoided.


Getting error while running sudo commands, from /etc/sudo.conf file

This is a situation where you need to use a live system image, use the same installation media.you need root privileges to fix this which you cannot access because Ubuntu by default locks the root user.
boot into the live image since Root has no password in live session,
then you need to do few steps
when you open the terminal type 'su' to run session using root user
1- mkdir /mnt create a directory then mount your root partition mount /dev/sdaX /mnt
2- chroot /mnt change the current root, this will let you install stuff in the system not in the live session.
3- apt --reinstall install sudo reinstall sudo
4- passwd -i root you can try activating the root user by configuring a password for it, this way the root user will be activated when you login next time. (acitvated only for CLI not GUI so press ctrl+alt+f* to login)
5-to enable the root user in the GUI , add the AllowRoot=true line in the [security] directive in file /etc/gdm3/custom.conf file.
and Add the # to comment the following line
auth required pam_succeed_if.so user !=root quiet_success
in /etc/gdm3/custom.conf file.
5- then umount and restart, when you login you can use root user and password
Edit:
if not possible to boot with live image , try the suggested solution for this issue in here


xrandr --output HDMI-1 --left-of VGA-1

or

xrandr --output HDMI-1 --right-of VGA-1

should do the trick


While configuring Compiz, GUI crashed. Only Desktop with icons and upper menu bar visible

I had the same experience last night and I was wondering what was going on. However,what I did was I simultaneously pressed CTRL+ALT+T to open the Terminal and type ccsm and the 'CompizConfig Setting Manager' popped up. I clicked to open OPENGL moved on to General and unticked 'Synch to VBlank' and Texture to Good from better.Ticked 'Ubuntu Unity Plugins' and closed it. I restarted my system and every icon came back as normal, I didn't know this unrelated thing how it solved the problem but it did. I would have done a system restore from the terminal but I had no backup. I hope you can find something useful from it. Thank you.

NB: After getting my normal Dektop back I uninstall CompizConfig Setting Manager for me not to accidentally repeat the same process. I think there is something with the CCSM that is responsible for that problem though.


Grub messed up after switching SATA ports - ubuntu boot loop

As I plugged in my HDD, as well, I was able to boot Kubuntu again. I now remember, that I configured /etc/fstab also to mount my data partition (by UUID) from my HDD...

I guess I could have saved me a lot of trouble, if I had plugged in my HDD from the beginning. :D


nobody and nogroup as directory owner when writing with php

Even though nobody and nogroup sounds special, they are more or less a regular system user (nobody) and a regular system group (nogroup), much like www-data

When your created files have these owners, then most likely your php is executed as nobody instead of www-data. Check you webserver configuration. It might be possible, that apache is run as nobody, or, more likely, that you use some kind of cgi/fastcgi setup (like mod_fastcgi or a php5-fpm.


How to run Desktop Entry command as a root (Exec=path)

I have the same problem.

I find out that the package gksu (gksudo) has been deprecated. first removed from Debian and then Canonical decided to drop it from Ubuntu 18.04. Application developers are suggested to use PolicyKit (pkexec) instead.

I suggest to look at this thread about using pkexec command in a .desktop file. I haven't try it yet (it looks a bit like an overkill for me and I don't want to mess sth up).

That's what I've got. Maybe someone else will have a better and simpler solution.


Compiling tar files without configure or readme files

In this particular case, the software does use the GNU Autoconf build system that results in the ./configure, make, make install recipe - but starts one step back by providing a configure.ac Autoconf input file rather than a ready-made configure script.

In general, configure is made from configure.ac using the autoconf program, sometimes using autoreconf to run additional configuration tools. In this case, that should be done by executing the provided autogen.sh script, so the recipe becomes

./autogen.sh
./configure
make

(and possibly)

sudo make install

For additional information about the Autotools build system, see A brief introduction to the GNU Autotools


The name of the systemd service is not nfsd (that's the name of the daemon process):

$ systemctl list-unit-files nfs*
UNIT FILE                 STATE
nfs-blkmap.service        static
nfs-config.service        static
nfs-idmapd.service        static
nfs-kernel-server.service enabled
nfs-mountd.service        static
nfs-server.service        enabled
nfs-utils.service         static
nfs-blkmap.target         disabled
nfs-client.target         enabled

9 unit files listed.

So the command to show the server status is

systemctl status nfs-server

or

systemctl status nfs-kernel-server


Transpose Album names for a bunch of MP3 files

sudo apt-get install tagtool

It's very easy to use. Just select the files and then edit their metadata.


Not able to type "=" and "-" characters in keyboard

It seems like your CTRL is pressed.

CTRL + perform Zoom In
CTRL - perform Zoom Out

The = and + are located on the same key in the keyboard, so when you press on = you actually press on +

Please try to release both CTRL by pressing on them a few times.

It might solve your problem


Simplest solution:

printf %.2f $(echo "$float/1.18" | bc -l)


run assudo  update-grub2 in your terminal to update the configuration.


You can not access any form of storage media without mounting the drive first. However, you can do this entire process from your terminal.
First, you need the partition ID (/dev/sdXY). You can use the lsblk command to find this. Once you have this ID, you can run sudo mount /dev/sdXY /mnt. Your flash drive's filesystem will now be available at /mnt and can be used from the terminal.
Devices in /dev are known as block devices, and are raw representations of the filesystems contained within those devices (where applicable). While you can directly read and write from these devices, it's often a bad idea because you're ignoring a huge layer of filesystem abstraction and protection.
For most use cases, the only time you'd be reading from/writing to the raw block devices is for cloning or very low level device operations. The filesystem provides a huge layer of abstraction, error checking, and file safety.

Note: The section below this block of text is meant for educational purposes only. Please do not try this on any system/drive that you care about, as the results could very easily be catastrophic. I take no responsibility for what you do if you follow anything I say below.
You have been warned.

With that warning being said, and if you don't care about the contents of your flash drive, it is theoretically possible to read and write data to/from the flash drive using raw block operations.
At its simplest, you'd write a file (let's say files.zip) to the flash drive using this command:
dd if=files.zip of=/dev/sdd bs=1024

This will copy the zipfile to your flash drive's raw block, but will also (likely) corrupt any partition or related data currently on the drive. It will also make a record of how many "blocks" were written to the drive -- make note of this. For this example, I'm going to say 1234 blocks were copied.
When you want to read the file from the flash drive onto another computer, you can do this with the inverse command:
dd if=/dev/sdd of=files.zip count=1234 bs=1024

This will pull the raw block data from the drive (containing a ZIP file) for the first 1234 blocks, and write it to files.zip on your computer in the current directory. Also note that this ZIP file may not be actually readable due to corrupt/garbage data at the end of the file or similar. Be sure to note this if necessary. You can use the head command to trim the ZIP file back if needed.
When you are done, you'll likely need to format the flash drive and re-partition it and the like, making this very infeasible for large operations. Just use the file system.


Why does ubuntu-bug imply that I shouldn't report bugs for Compiz and Unity?

I mailed Brian Murray (the Ubuntu bugmaster) about this:

  Thanks for bringing this up.  Its news to me and I'm not really happy
  with the user experience here.  Digging into it this is actually the
  Xorg package hook for apport so using ubuntu-bug with an Xorg package
  will provide essentially the same experience.  Maybe we should sit down
  with Bryce next week and discuss it?

Maybe a good start here would be to file a bug on the xorg package about the apport hook. I'll follow up at UDS and update this answer.

(Nice catch by the way!)


I've had a few issues like this with various things. I find the best way to fix these is to write a little shell script and stick it in ~/bin.

Here's what I did for Nexuiz (which had some path issues):

#!/bin/bash
cd ~/Nexuiz
./nexuiz-linux-x86_64-sdl

You obviously don't want that path or that executable but basically cd to the right place and then run it.

Don't forget to chmod +x the script. And then just have your launcher call the script.

Your script should look like this:

#!/bin/bash
cd /home/will/Machinarium
./Machinarium


Shelled root seems to print incorrect from /etc/shadow | grep root

OK, so in this case it would seem as if it all boiled down to the child.before print in send_command.

Printing out the child object I could see that there were a few key-value pairs that I should have grabbed, one of which (buffer) holds the 100 last characters of the grep. This isn't the full encrypted password, but at least some of them.

So, if you do find yourself in a similar problem simply print the child and check what the output is!


Ubuntu 12.04 won't load on Windows 8 + DELL Inspiron 14z

Preinstalled Windows8 are always in UEFI mode.
You have installed Ubuntu inside Windows (via the Wubi installer), but unfortunately Wubi is not compatible with UEFI.

So you should not use Wubi, but install Ubuntu the standard way. See https://help.ubuntu.com/community/UEFI for more information.


How to read and write HFS+ journaled external HDD in Ubuntu without access to OS X?

See How to mount a HFS partition in Ubuntu as Read/Write? - Super User

To quote from the second/third answer down:

  First, make sure that you have hfsprogs installed. Example
  installation command:

  sudo apt-get install hfsprogs

  Next, mount or remount the HFS+ drive; commands need to be as follows:

  sudo mount -t hfsplus -o force,rw /dev/sdXY /media/mntpoint

  or

  sudo mount -t hfsplus -o remount,force,rw /mount/point

...

  Finally, if the drive was improperly unmounted or has otherwise become
  partially corrupted run fsck.hfsplus ... as
  such:

  sudo fsck.hfsplus -f /dev/sdXY

There is a goldmine of other information there regarding the mounting of HFS+ filesystems.


Can't get Netbeans to stay locked to launcher?

You have to use a program called "MainMenu" for this, (I think it is installed by default with 12.04 LTS) if not installed you can install it from the application store.

After loading MainMenu, click the "Add new item" button and follow the screen instructions. So simple.


Need application/script alerting when system memory is running out

You could try using free.

free -s n will update the output every n seconds. Wrap that in an if for whatever threshold you feel is "too much memory" being used, and display a message when it reaches that point.

EDIT: Here's the script I came up with. Rough, but it works.

#Checks for low memory.

#!/bin/bash

#cutoff_frac is basically how much used memory can be at in terms of how much
#total memory you have...2 is 1/2 of 100% or an alert when you're using 50% mem, etc.
cutoff_frac=2

total_mem=$(free|awk '/^Mem:/{print $2}')
let "threshold = $total_mem / $cutoff_frac"

while :
do

    free_mem=$(free|awk '/^Mem:/{print $4}')

    if [ $free_mem -lt $threshold ]
        then
        notify-send "Low memory!!"
    fi

    sleep 5

done

exit


Replace Black screen/kernel text compiling with image

I think you want to change that black background color in grub menu.

if so, see it http://www.upubuntu.com/2012/03/how-to-change-grub2-background-image.html


Website, SFTP, SSH in home directory for multiple users

Have you considered adding the users who need access to the www-data group? I am fairly certain that apache runs as www-data on Ubuntu 14.04. If you add the users to this group you wont have to mess with chmod on that folder - which always has the potential to break apps that are currently in use.


How to list all packaged installed/upgraded from '-proposed'?

I made a script which should at least list them up:

#!/bin/bash
search="proposed"
for name in $(apt-cache search '' | sort -d | awk '{print $1}')
    do
    pkg="$(apt-cache policy "$name")"
    if [ "$(grep "(none)" <<<"$pkg")" == "" ] && [ "$(grep "$search" <<<"$pkg")" != "" ]
        then
        pkn="$(echo "$pkg" | head -n 2)"
        source=$(grep "$search" <<<"$pkg" | awk '{print $2" "$3" "$4;}')
        echo "$pkn"
        echo "$source"
        echo
    fi
done

You can check that it works if you change proposed to main.


What do I use for the pxe boot file for MAAS nodes?

filename "/pxelinux.0";

should do it. The files are looked up in the tftp server's root area, which is /var/lib/tftpboot

How do I modify the pxe config in MAAS?


Where do I find packages files of apps that are installed

From the comment to @DannyStaple I understand you look for different information.

If you want to know where apt-get download the (unpacked) packages you install, have a look in

/var/cache/apt/archives

This directory could become very big, so feel free to remove the content by hand, or preferably by issuing the command

sudo apt-get clean

Moreover, if you want to know were are the files unpacked from the package you installed, the following command give you the list

dpkg -L package-name

In particular, appending | grep /bin/ will show only the real program(s), and | grep /man/ or | grep /doc/ will show the manual pages or the documentation files.

As a last note, there is no need to backup installed packages, they could be simply reinstalled from repos.

If you do some modification to system configuration files (those residing in /etc), backup only them. User configuration files reside in hidden files and directories in your home, so a home backup is enough.


alsa driver compiled with errors 12.04.02 LTS

The 1.0.25 driver package is outdated.

The drivers are part of kernel; to update the drivers, just update the kernel.


Kernel panic in version 3.0.0-13 prevents login ("VFS not syncing" error)

I had the same issue. I chose older versions instead of safe mode at boot and selected the previous kernel 3.0.0.12. Now the system runs fine, but at next boot, 3.0.0.13 will again be the default. Therefore, I removed the all kernel packages found with the string "3.0.0.13" in synaptic package manager.


Ubuntu 14.04: no sound card detected AMD

Well ... doing Ubuntu updates did the trick. I hadn't done that in a while...


Lubuntu 14.04. Copy DVD between two DVD drives

K3B uses Qt, but this doesn't mean that it is restricted purely to KDE. It should work in all window managers. As you don't mention specifics with regard to what problems you're experiencing with K3B I can't help you with that.

However, if K3B doesn't work for you, you can always use AcetoneISO, being a suitable alternative to K3B in your case.


Not able to disable Airplane mode on Ubuntu 16.04

The driver for the apparently inoperative internal device may be interfering. Let's unload it and blacklist it. Please open a terminal and do:

sudo -i
modprobe -r rt2800pci
echo "blacklist rt2800pci"  >>  /etc/modprobe.d/blacklist.conf
exit

You should be all set.


404 Not Found Error on every page other than index.html

Try enabling mod_rewrite with sudo a2enmod rewrite.

You can also try checking any config files in /etc/apache2/sites-enabled and ensuring that AllowOverride is set to All and not none.

After either or both is done, restart Apache with sudo service apache2 restart.


Ubuntu 16.04 | Can't log back in from suspend after kernel update using GNOME 3 (NVIDIA)

This is not the solution I was hoping for. Either way... I had to downgrade my kernel to 4.4. At the time I didn't know that installing newer versions, (not stable, mainline? I don't really know), were to crash especially drivers concerning graphics. So as a matter of fact it was a problem with Nvidia and after trying different versions of the same driver I decided, since nothing much changed since my kernel update, I should maybe go back to the old, stable one.

How I changed the kernel:
https://askubuntu.com/a/142000/742966

And removing the "newer" one was a matter of sudo apt-get remove linux-image-4.13.8-041308-generic and sudo update-grub


Desktop Environment not working - Black screen, no mouse

A crash or poweroff during the install part of a release upgrade is the time when your system is most vulnerable. The mix of old and new packages are incompatible, and can leave your system broken in a wide range from completely unbootable to fiddly little annoyances.

If you are expert, you can sometimes use clever tools (like a chroot) to complete the upgrade. However, for most users, repair is too complex or otherwise simply not worthwhile.

For most users: Create a LiveUSB using a different machine, then backup your data, then reinstall fresh.


What alternatives to Nautilus exist which are more responsive?

Thunar file manager is designed to be fast, lightweight, and easy-to-use.

To install Thunar in Ubuntu 12.10, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below:

sudo apt-get install thunar

For Ubuntu 12.04, add the Xfce 4.12 PPA.  To do so, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below:

sudo add-apt-repository ppa:xubuntu-dev/xfce-4.12
sudo apt-get update && sudo apt-get upgrade
sudo apt-get install thunar


From a similar question on Super User:

Generally speaking, you can hibernate one operating system and boot the other. Each system's state is saved in its own swap space, so you must not share the swap space between the two operating systems.

There's one thing you must pay attention to: while a partition is mounted in a hibernated operating system, you must not access it from other operating systems. With most filesystems, this is likely to destroy your data. (This doesn't apply to network filesystems mounted from another machine, these are designed to be mounted from multiple places at once.) Exception: if the shared partition is NTFS and it's not the Windows boot partition, it's safe to share at the filesystem level (but you'd better not keep a file open in a hibernated application, so it's better to unmount the shared partition before hibernating anyway).


Error importing lxml package python in Ubuntu

According to your answer to a different question, you have a python interpreter in /usr/local/bin.

As musher pointed out it could not have been compiled to support ucs4. Try with the version installed in /usr/bin instead.


We found that a 3rd party web app was managing it's own session files and failing garbage collection.  Once we deleted some very old folders of them, the issues disappeared.


What is the current best way to dual boot a Mac with Ubuntu on the latest 10.12 macOS?

I spend the last 3 nights searching every corner of the web for a straightforward guide how to dualboot the latest macOS 10.12 Sierra with Ubuntu, but it seems like there is just so many ways people recommend doing, that in other forums people are advising against at.

You're running into the paradox of choice -- too many options on this matter are creating confusion. In reality, it's hard to say that any one option in this specific issue is really any better than any other option, except in fitting certain very specific goals, most of which you haven't mentioned any preferences on, except:

  My ideal scenario would of course be to select either macOS or Linux via the alt-Key in Apple's standard bootloader.

In this case, the solution to which you linked makes sense, although I suspect it may be a little bit overly-complex in a couple of points. (I'm not 100% positive of that, though.)

Note, however, that the screen you see when you hold down the Alt/Option key when booting a Mac is not a boot loader; it's a boot manager. You're still relying on separate boot loaders (Apple's boot.efi file to boot macOS or GRUB to boot Linux) to boot the computer. This is, in some sense, a minor matter of terminology; but it's important to understand that boot managers are user interface tools whereas boot loaders load kernels into memory and execute them, since in some contexts this distinction is very important. Unfortunately, people tend to be sloppy about this distinction.

  every new version of macOS (especially since the integration of SIP in El Capitan) appears to change the way it handles the booting process and the majority of articles regarding this subject is older than 10.11, which makes me feel a bit lost at the the moment.

Yes, the ever-changing nature of macOS booting can be a problem. I recommend you begin by ignoring anything that suggests installing Linux in BIOS/CSM/legacy mode. Although doing this is sometimes necessary, that's rarely the case today. Broadly speaking, you're then left with two choices:

What to use as a boot manager -- Above, you expressed a preference for the Mac's built-in boot manager. This tool is limited, but you know it's already present in the computer. The two major alternatives are GRUB 2 (which is installed by Ubuntu, but I've seen few discussions of using it to boot macOS) and rEFInd (which you're obviously aware is a popular choice on Macs). rEFIt used to be a good alternative, too, but it's been abandoned for years, so rEFInd (which I forked from rEFIt) is a better choice.
What to use as a boot loader -- Both the method you cited and any method that uses GRUB as a boot manager are likely to use GRUB as the boot loader, too. rEFInd can do the same, but rEFInd can also use the EFI stub loader, which is a kernel feature that turns the Linux kernel into its own boot loader.

Note that GRUB is both a boot manager and a boot loader. rEFInd, OTOH, is technically only a boot manager; but the existence of the EFI stub loader (which is technically a boot loader but not a boot manager) enables rEFInd to act like a boot loader of Linux kernels.

  My biggest concern regarding rEFInd is the malfunctioning of the hibernation feature other users complain about.

This was a big problem a while back, but I haven't seen any recent complaints about it, so I believe that the current defaults in refind-install fix this problem. As you suggest, installing rEFInd to a separate HFS+ partition is one reported solution, so you could always try that if you install rEFInd to the ESP and then run into problems.

It's possible to switch boot managers and loaders even after you've installed everything. On this specific issue, if you decide to use rEFInd, you can hedge your bets a bit by setting aside a ~200 MiB partition. Don't even put a filesystem on it initially. Install rEFInd using its defaults, which will put it on the ESP. If you have problems, you can then put an HFS+ filesystem on the small spare partition and re-install rEFInd to it. If this resolves the problem, great. If not, you can put GRUB 2 on the small HFS+ partition in a variant of the method described in on the page to which you linked.

  install Ubuntu, reformat the main Linux partition and select the swap partition (do I have to change the location for the bootloader installation?)

If the Ubuntu installer runs in EFI mode, it will install GRUB 2 to the ESP. If there's even a prompt for where to install the boot loader, it's ignored in EFI mode.

It's also worth pointing out that, if you intend to use rEFInd and the EFI stub loader, you can launch the Ubuntu installer by booting into "try before installing" mode, open a Terminal window, and typing ubiquity -b. The -b option tells the installer to not install GRUB. This will minimize the chance of a boot coup in the future, and it will prevent GRUB from running time-consuming scripts whenever the kernel is updated to modify its configuration files (which you wouldn't be using if you're not including GRUB in the boot process).

  I have read that installing rEFInd on the a seperate hfs partition would fix the hibernation issue. In this case, do I have to select/reformat the little hfs partition as an EFI system partition during the Linux install (like David Anderson suggests)?

No. Technically, an ESP must use the FAT filesystem. In practice, a Mac's firmware doesn't care whether a partition is marked as an ESP or as a standard HFS+ partition when it launches a boot loader.

I should also point out that I don't see the point of creating a second ESP in the instructions to which you've linked. Maybe I'm missing something, though.

  Even if would I do everything the default way (including the risk of the hibernation issue), what are the correct partition choices while installing Ubuntu? Do I need to define an new EFI system partition in this case, or not at all?

No, the ESP is intended to be shared by all the OSes on the computer. In the case of Macs, though, Apple uses it only for firmware updates, AFAIK; its boot loader resides on its Recovery HD volume.

That said, you can create multiple ESPs; doing so is legal and, AFAIK, all EFIs support such configurations. There's just little or no point to doing so.


Installing snap package in encrypted home folder?

This is a known issue and it has been fixed in the packages available from the xenial-proposed repo. If you just want the fix without enabling proposed, you can install the snap-confine and ubuntu-core-launcher from the repo, both are available at https://launchpad.net/ubuntu/+source/snap-confine/1.0.38-0ubuntu0.16.04.4 .

The bug is reported here: https://bugs.launchpad.net/ubuntu/+source/snapd/+bug/1592696


I tried out touchegg today and had the same experience with it not working. It turned out I had to disable some multi-touch gestures that were hardcoded into the system before it would work. How to do this is explained in this response from another thread: How can I disable arbitrary default multitouch gestures in Unity?

After I did that touchegg actually worked fine.

Hopefully future releases of unity will allow to modify the multitouch gestures in the system settings, as it seems the functionality is already there.


How can I use the previous command's output?

First of all, to delete all files with the .class extension, you don't need anything more than:

rm *.class

In any case, as a general rule, you really shouldn't try to parse the output of ls. It will fail for pretty much any strange filename.

For future reference, to iterate over the results of a command, use a while loop. For example:

command | while read i; do rm "$i"; done


What is the solution to laggy scrolling on a computer with low specs?

Before trying 10.04, why don't you try a Live CD (or USB) of lighter derivatives of Ubuntu such as Xubuntu 12.04 or Lubuntu 12.04?

Even then, you may face problems with browser performance because most browsers and web pages seem to assume modern hardware and ample RAM.

Also, keep in mind that the end of support for 10.04 isn't too far off: April 2013. You can read more on the implications here.


Ubuntu 16.04 blank screen after boot, AMD APU

You may try adding nomodeset quiet splash to

  /etc/default/grub

I found that this worked, although I also had to specify the default resolution of my laptop GRUB_GFXMODE=1920x1080 to get it to work satisfactorily. Remember to sudo update-grub to get it to work on every boot.

There was also a post about the difficulties in using the AMD driver and 16.04

I am using a HP Pavilion based AMD-APU on 64bit 16.04


Grub loader comes up instead of Ubuntu login screen

I also had a problem, where I couldn't load Ubuntu.

The solution was to boot from rEFInd boot manager from Rod Smith and copy a .efi-file named grubx64.efi from the /boot/efi/EFI/ubuntu-directory to the /boot/efi/EFI/Boot-directory and rename it to bootx64.efi.

If this is not the solution, you may still be able to boot into ubuntu with the rEFInd boot manager!

Good luck!


Audio not working in Ubuntu 20.04 after switching over from dual-booted OS (Solution)

You don't need to modify any config files or anything. Just put your PC to sleep by either manually putting it to sleep or just closing it if its a laptop. Wait for about 20 seconds and then open it/start it up again. It should work now. Don't restart it or anything. I had this issue and this worked just fine for me. I hope I could help


Regarding to this list of files: http://packages.ubuntu.com/precise/amd64/imagemagick/filelist

You should use this values.

$wgImageMagickConvertCommand = /usr/bin/convert
$wgImageMagickIdentifyCommand = /usr/bin/identify


Browsing through packages available for installation in Synaptic, I found something called pop3browser. From the description:
Allows one to check a pop3 mailbox before downloading any mail
pop3browser is intended to delete unwanted (SPAM) mails before downloading via a low-bandwidth connection. This is useful to save time, bandwidth and space.
You may give it a try.


Cannot execute QT console program in ubuntu

It says Permission denied, i.e. you do not have the permission to run this program.

You will need to set the executable bit with command chmod +x /media/milo/DATA1/Milo/C++/build-test-Desktop-Debug/test

There is the catch though. It looks like the program is on a USB stick. If that stick is formatted as vfat filesystem then you may not be able to set the execution bit. If this is the case copy the program to your home folder (or another folder on an ext2/3/4 partition), set the execution bit there and run it.


Is it Possible to create a desktop shortcut for the Sage Notebook?

You can create a shortcut that runs the command sage -n or sage -notebook.


Why doesn't Ubuntu remove old kernels automatically?

Is there a reason why Ubuntu wont do this automatically?

I can see only 1 reason: it does not work flawlessly; there is no clean way to currently decide what the definition of "old kernels" is. "old" does not mean "unused" nor does it mean "unwanted".  And any mistake in this will kill a users' machine.
So up to now the manual method is preferred since this puts the power of removing into the users' hands.

Resources for this conclusion:

Ubuntu WIKI: Proposal for removing old kernels
Last-good-boot is implemented fully in Intrepid/8.10 final, however it has been disabled because it was not considered stable enough. The setting is a single line in the file /etc/default/kernel-helper-rc.

Launchpad: Should aptitude provide a way to remove old kernel versions ?
apt-get has an autoremove feature that uninstalls all packages that are not needed as dependencies and have not been installed manually. Since Ubuntu 14.04 all obsolete kernels and headers should automatically be flagged as no more needed, and thus can be purged with the apt-get autoremove command. (There are reports that this does not yet fully work). I am not aware of a feature in aptitude that is similar to apt-get's autoremove.

Ubuntu-devel: Distro-provided mechanism to clean up old kernels
While agreeing that it would be quite helpful and seems appropriate to have the
cleanup automatic, there is a slight potential pitfall (or two). There are
various flavours of kernels and people may or may not deliberately have those
installed in parallel. Also various releases had sometimes a changing set of
depending packages. For a while this should be only linux-backports-modules
(there had been linux-ubuntu-modules and linux-restricted-modules). Though this
is not so much of a problem.
From a pattern matching point of view the generic-pae kernels are a bit of a
pain as they tend to ruin the "use the last part of a split by "-" for the flavor".
But anyway, I think the main issue is the various flavours, so a cleanup that is
automatic should retain the last three of each, even though this may tend to
leave more kernels around.


Is Ubuntu 10.04 compatible with Toshiba L640D

I have a very similar configuration on my lenovo z560. the only difference is that it uses nvidia instead of ati. Ubuntu installed without a glitch. so i dont think there would be any problem. Of Course if you do run into one you can always ask here :D


The 'Bookmarks', perhaps more correctly known as 'Favorites' in Xenial's SMPlayer version 15.11.0, are stored in the following path:

~/.config/smplayer/favorites.m3u8

This single file can be easily backed up to the media of your choice. For example on my own setup I backup to an external USB drive:

andrew@ilium~$ cp -v ~/.config/smplayer/favorites.m3u8 /run/media/andrew/CORSAIR/
'/home/andrew/.config/smplayer/favorites.m3u8' -> '/run/media/andrew/CORSAIR/favorites.m3u8'
andrew@ilium~$

Easy :)


How to install Google Docs extension in Libreoffice?

I installed ooo2gd the following way. Install JRE and libreoffice-java-common

sudo apt-get install default-jre libreoffice-java-common

Then download ooo2gd latest and do

unopkg add PATH/ooo2gd_3.0.0.oxt

Then start Libreoffice.


brightness settings on Ubuntu 11.10 64bit, Hardware Dell 1555 with ATI Mobility Radeon HD4570

I have found that disabling the "Varibright" option under power management in the AMD Control Center fixes the brightness problem.  I've never really measured what effect turning it off has on batter life, but I still get great battery life so I'm thinking the effect is minimal.


Why Grub does not Recognize Two USB sticks in 16.04?

Choose a computer which has new Bios that is graphical. I could not get the prioritizing work with older PCs having the textual Bios. However, the prioritizing works in the newer Bioses. Probably, just Grub2 is enough.


ok, so after trying with ethernet port and after the help from 2707974 I managed to solve the problem. apparently metric 0 was the problem, the ethernet interface worked allright and the metric value was 1, so i changed the metric value of the wlan interface and everything got back to normal, to change that I used:

sudo ifmetric wlan0 1