<p>I'm having some problems getting any incoming connections in Bitcoin Core (v0.15.0.1).</p>

<p>I have verified that the machine running the client can receive incoming connections on port 8333 over both IPv4 and IPv6, and upon doing so, the remote IP shows up as a peer (which doesn't do anything because I'm only connecting via telnet to confirm the open port.)</p>

<p>However I am not getting any incoming connections from the network, over IPv4 or IPv6.  I thus only have 8 outgoing connections and the network speed is extremely slow, so it is taking forever to catch up to the latest block (client is telling me two weeks catch up time.)</p>

<p>When I run the <code>getnetworkinfo</code> command in the console, it tells me both <code>ipv4</code> and <code>ipv6</code> networks are reachable, however the <code>localaddresses</code> only shows my IPv6 address:</p>

<pre><code>"networks": [
  {
    "name": "ipv4",
    "limited": false,
    "reachable": true,
    "proxy": "",
    "proxy_randomize_credentials": false
  }, 
  {
    "name": "ipv6",
    "limited": false,
    "reachable": true,
    "proxy": "",
    "proxy_randomize_credentials": false
  }, 
  {
    "name": "onion",
    "limited": true,
    "reachable": false,
    "proxy": "",
    "proxy_randomize_credentials": false
  }
],
"localaddresses": [
  {
    "address": "2001:4479:xxxx",
    "port": 8333,
    "score": 1
  }
],
</code></pre>

<p>Shouldn't <code>localaddresses</code> also show my IPv4 address?  I'm behind a NAT for IPv4 but the port forward works, and the usual show-my-ip places report the correct global IP which does reach this machine on port 8333.</p>

<p>Although I have an outgoing connection to an IPv6 client, I am wondering whether the problem is that 1) there are not many IPv6 clients and 2) the client is not advertising my IPv4 address.</p>

<p>Does the client stop advertising IPv4 addresses when IPv6 ones are available?  Or is there another reason why no IPv4 address would be showing?</p>

<p>EDIT: Ran <code>bitcoind</code> and this is what it says about the network:</p>

<pre><code>...
torcontrol thread start
AddLocal([2001:4479:xxxx]:8333,1)
Discover: IPv6 eth0: 2001:4479:xxxx
Bound to [::]:8333
Bound to 0.0.0.0:8333
init message: Loading P2P addresses...
Loaded 48551 addresses from peers.dat  117ms
init message: Loading banlist...
init message: Starting network threads...
...
</code></pre>

<p>Looks like it's only discovering IPv6 and not IPv4 for some reason.</p>

CC BY-SA 3.0
2017-11-05T02:40:29.390Z
The speed of sync is unrelated to your number of peers, in many cases more peers will actually make it slightly slower. The sync is entirely bound to the amount of CPU and IO speed available to `bitcoind`.
Claris
CC BY-SA 3.0
2017-11-05T04:02:52.590Z
@eponymous: So then why is my CPU idle and my network going at < 1kB/sec, but the client says there's still two weeks to go until the blockchain is up to date?  If my CPU and disk aren't being used and I'm still behind, then it would appear that the blockchain history isn't coming in fast enough over the network, unless I'm missing something?
Malvineous
CC BY-SA 3.0
2017-11-05T05:18:20.627Z
Bitcoin makes a lot of effort to have only high quality peers (punting those that don’t provide fast or useful information), this suggests that there are problems with your connection globally rather than your peers.
Claris
CC BY-SA 3.0
2017-11-05T08:10:05.793Z
@eponymous: What sort of problems?  I've never noticed any issues with other protocols - Tor works fine, BitTorrent has no issues with incoming connections, upload/download rates are good, SSH is low latency - everything seems fine as far as I can tell.
Malvineous
<network>
Why no IPv4 incoming connections when IPv6 available?
Malvineous
# Why no IPv4 incoming connections when IPv6 available?

(Asked by: username_0 on 2017-11-05)

I'm having some problems getting any incoming connections in Bitcoin Core (v0.15.0.1).

I have verified that the machine running the client can receive incoming connections on port 8333 over both IPv4 and IPv6, and upon doing so, the remote IP shows up as a peer (which doesn't do anything because I'm only connecting via telnet to confirm the open port.)

However I am not getting any incoming connections from the network, over IPv4 or IPv6. I thus only have 8 outgoing connections and the network speed is extremely slow, so it is taking forever to catch up to the latest block (client is telling me two weeks catch up time.)

When I run the `getnetworkinfo` command in the console, it tells me both `ipv4` and `ipv6` networks are reachable, however the `localaddresses` only shows my IPv6 address:

```
"networks": [
  {
    "name": "ipv4",
    "limited": false,
    "reachable": true,
    "proxy": "",
    "proxy_randomize_credentials": false
  }, 
  {
    "name": "ipv6",
    "limited": false,
    "reachable": true,
    "proxy": "",
    "proxy_randomize_credentials": false
  }, 
  {
    "name": "onion",
    "limited": true,
    "reachable": false,
    "proxy": "",
    "proxy_randomize_credentials": false
  }
],
"localaddresses": [
  {
    "address": "2001:4479:xxxx",
    "port": 8333,
    "score": 1
  }
],

```

Shouldn't `localaddresses` also show my IPv4 address? I'm behind a NAT for IPv4 but the port forward works, and the usual show-my-ip places report the correct global IP which does reach this machine on port 8333.

Although I have an outgoing connection to an IPv6 client, I am wondering whether the problem is that 1) there are not many IPv6 clients and 2) the client is not advertising my IPv4 address.

Does the client stop advertising IPv4 addresses when IPv6 ones are available? Or is there another reason why no IPv4 address would be showing?

EDIT: Ran `bitcoind` and this is what it says about the network:

```
...
torcontrol thread start
AddLocal([2001:4479:xxxx]:8333,1)
Discover: IPv6 eth0: 2001:4479:xxxx
Bound to [::]:8333
Bound to 0.0.0.0:8333
init message: Loading P2P addresses...
Loaded 48551 addresses from peers.dat  117ms
init message: Loading banlist...
init message: Starting network threads...
...

```

Looks like it's only discovering IPv6 and not IPv4 for some reason.

**Tags:** network

> **Comments:**
> **username_1**: The speed of sync is unrelated to your number of peers, in many cases more peers will actually make it slightly slower. The sync is entirely bound to the amount of CPU and IO speed available to `bitcoind`.  
> **username_0**: @eponymous: So then why is my CPU idle and my network going at < 1kB/sec, but the client says there's still two weeks to go until the blockchain is up to date?  If my CPU and disk aren't being used and I'm still behind, then it would appear that the blockchain history isn't coming in fast enough over the network, unless I'm missing something?  
> **username_1**: Bitcoin makes a lot of effort to have only high quality peers (punting those that don’t provide fast or useful information), this suggests that there are problems with your connection globally rather than your peers.  
> **username_0**: @eponymous: What sort of problems?  I've never noticed any issues with other protocols - Tor works fine, BitTorrent has no issues with incoming connections, upload/download rates are good, SSH is low latency - everything seems fine as far as I can tell.  

---

## 0 answers

