<p>Your node should try and make 8 outbound connections to other nodes first. Forwarding port 8333 is just to allow incoming connections and is not required for your node to sync up.</p>

<p>So, thinking first of connectivity you should work through the basics:</p>

<p>Restart your modem and router equipment. Shut down bitcoind with <code>&gt;bitcoin-cli stop</code>. Reboot your Ubuntu host and reboot your Docker session, restart bitcoind.</p>

<p>Can you resolve DNS queries from your Docker session, can you make successful HTTP requests from your Docker session (curl down some file or wget)? Can you <code>&gt;nmap seed.btc.petertodd.org -p 8333</code> which doesn't always work first try, it is a DNS round robin - just try several times is enough you should get at least one success.</p>

<p>After network connectivity is resolved, you may wish to check out <a href="https://bitcoin.stackexchange.com/questions/58369/sync-with-bitcoin-qt-very-slow-0-01/69862#69862">this answer</a> for some more information.</p>

CC BY-SA 3.0
2018-02-16T10:10:26.720Z
Hey thanks for all the suggestions and advice, I turned off the firewall for now. I have enabled port forwarding yet some how still my btc traffic is filtered found out that with this command "nmap seed.btc.petertodd.org -p 8333" provided by @willtech, Any way found the issue its the firewall I am going to look into it in more detail
f4r4
CC BY-SA 3.0
2018-02-16T08:47:11.713Z
2018-02-16T08:47:11.713Z
Willtech
<p>You won't be able to sync without having any connections. The problem is that you have 0 connections; make sure that you don't have any firewalls (either in your docker container, the host, your router, or your ISP) that is blocking Bitcoin traffic.</p>

CC BY-SA 3.0
2018-02-16T05:09:33.530Z
It was running very slowly its 3 weeks and I have 300k blocks but suddenly everything stopped, as I described in my update port 8333 is still open and accessible deom 3rd party port checkers but not accessible from bitnodes checker
f4r4
CC BY-SA 3.0
2018-02-16T05:23:23.127Z
Again, make sure that there is not anything blocking the connection. Even if it was working a few weeks ago, your ISP could have changed something that blocked it. Or an update to your OS or other software may change your computer's firewall.
Ava Chow
CC BY-SA 3.0
2018-02-16T06:42:42.277Z
I checked everything ISP - Not blocked , Ubuntu Iptables - Not Blocked, Docker Container - Not Blocked 

can anyone tell me the steps to diagnose this issue ?  or its useless running this full node Im going to quit
f4r4
CC BY-SA 3.0
2018-02-13T05:22:51.620Z
2018-02-13T05:22:51.620Z
Ava Chow
<p>I have a server with 32 Gigs of ram and running the node on a docker container using Bitcoin Core Daemon version v0.15  with 8333 ports mapped </p>

<p>Nodes been running for 2.5 weeks still 300k blocks and most of the time connectioncount is 0, only once I saw it jumped up to 60
I even increased the dhcache</p>

<p>why is it taking so long ? How do I speed things up ? for most of the guys it took only 1-2 weeks </p>

<hr>

<p><strong>Update</strong>
01- This is my setup 
<a href="https://i.sstatic.net/dakF7.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/dakF7.png" alt="enter image description here"></a></p>

<p>02- It was working fine and when I checked weather ports are open from outside network before 300k sync
I - <a href="https://www.yougetsignal.com/tools/open-ports/" rel="nofollow noreferrer">https://www.yougetsignal.com/tools/open-ports/</a> 
Two weeks before 8333 OPEN 
Now 8333 OPEN</p>

<p>II - <a href="https://bitnodes.earn.com/#join-the-network" rel="nofollow noreferrer">https://bitnodes.earn.com/#join-the-network</a>
Two weeks before 8333 OPEN and Reachable
<strong>NOW unreachable</strong> </p>

<p>III- Connection speed 10 MB</p>

CC BY-SA 3.0
2018-02-12T20:10:37.017Z
would you happen to know the bandwidth limits of your node's ISP?
Tony Rizko
CC BY-SA 3.0
2018-02-12T21:08:33.843Z
Don't forget that you are downloading 150GB From different nodes. It took four days with me with a good internet connection and 16GB ram. If your donwload speed 33mb per second, it will takes 82,5 hour if all nodes upload speed 33mb per second.
Tailer
CC BY-SA 3.0
2018-02-13T11:49:27.677Z
It would be useful for considering what the issue may be if you could please edit your question to explain more about your network configuration, how connections are routed to the public internet, your connection speed and type and, any other useful information.
Willtech
CC BY-SA 3.0
2018-02-13T12:09:30.100Z
Additionally, details of your Bitcoin Core configuration may be useful, what parameters you use on the command line and your `bitcoin.conf` file.
Willtech
CC BY-SA 3.0
2018-02-16T05:03:20.527Z
I did not do any changes to my conf file
f4r4
<bitcoin-core><bitcoind><nodes>
BTC full node very slow block downloads
f4r4
# BTC full node very slow block downloads

(Asked by: username_0 on 2018-02-12)

I have a server with 32 Gigs of ram and running the node on a docker container using Bitcoin Core Daemon version v0.15 with 8333 ports mapped

Nodes been running for 2.5 weeks still 300k blocks and most of the time connectioncount is 0, only once I saw it jumped up to 60
I even increased the dhcache

why is it taking so long ? How do I speed things up ? for most of the guys it took only 1-2 weeks

---

**Update**
01- This is my setup
[![enter image description here](https://i.sstatic.net/dakF7.png)](https://i.sstatic.net/dakF7.png)

02- It was working fine and when I checked weather ports are open from outside network before 300k sync
I - <https://www.yougetsignal.com/tools/open-ports/>
Two weeks before 8333 OPEN
Now 8333 OPEN

II - <https://bitnodes.earn.com/#join-the-network>
Two weeks before 8333 OPEN and Reachable
**NOW unreachable**

III- Connection speed 10 MB

**Tags:** bitcoin-core, bitcoind, nodes

> **Comments:**
> **username_1**: would you happen to know the bandwidth limits of your node's ISP?  
> **username_2**: Don't forget that you are downloading 150GB From different nodes. It took four days with me with a good internet connection and 16GB ram. If your donwload speed 33mb per second, it will takes 82,5 hour if all nodes upload speed 33mb per second.  
> **username_3**: It would be useful for considering what the issue may be if you could please edit your question to explain more about your network configuration, how connections are routed to the public internet, your connection speed and type and, any other useful information.  
> **username_3**: Additionally, details of your Bitcoin Core configuration may be useful, what parameters you use on the command line and your `bitcoin.conf` file.  
> **username_0**: I did not do any changes to my conf file  

---

## 2 answers

### Answer by username_3 on 2018-02-16. Score: 0 | Accepted answer

Your node should try and make 8 outbound connections to other nodes first. Forwarding port 8333 is just to allow incoming connections and is not required for your node to sync up.

So, thinking first of connectivity you should work through the basics:

Restart your modem and router equipment. Shut down bitcoind with `>bitcoin-cli stop`. Reboot your Ubuntu host and reboot your Docker session, restart bitcoind.

Can you resolve DNS queries from your Docker session, can you make successful HTTP requests from your Docker session (curl down some file or wget)? Can you `>nmap seed.btc.petertodd.org -p 8333` which doesn't always work first try, it is a DNS round robin - just try several times is enough you should get at least one success.

After network connectivity is resolved, you may wish to check out [this answer](https://bitcoin.stackexchange.com/questions/58369/sync-with-bitcoin-qt-very-slow-0-01/69862#69862) for some more information.

> **Comments:**
> **username_0**: Hey thanks for all the suggestions and advice, I turned off the firewall for now. I have enabled port forwarding yet some how still my btc traffic is filtered found out that with this command "nmap seed.btc.petertodd.org -p 8333" provided by @username_3, Any way found the issue its the firewall I am going to look into it in more detail  

---

### Answer by username_4 on 2018-02-13. Score: 2

You won't be able to sync without having any connections. The problem is that you have 0 connections; make sure that you don't have any firewalls (either in your docker container, the host, your router, or your ISP) that is blocking Bitcoin traffic.

> **Comments:**
> **username_0**: It was running very slowly its 3 weeks and I have 300k blocks but suddenly everything stopped, as I described in my update port 8333 is still open and accessible deom 3rd party port checkers but not accessible from bitnodes checker  
> **username_4**: Again, make sure that there is not anything blocking the connection. Even if it was working a few weeks ago, your ISP could have changed something that blocked it. Or an update to your OS or other software may change your computer's firewall.  
> **username_0**: I checked everything ISP - Not blocked , Ubuntu Iptables - Not Blocked, Docker Container - Not Blocked   can anyone tell me the steps to diagnose this issue ?  or its useless running this full node Im going to quit  

---

