Possible firewall problem with ubuntu server and bitcoind

[Fr0stst0rm]

Hello. I have an ubuntu server on which several VMs are running  and I want to use one VM as Bitcoin Node. I installed everything according to the tutorial on bitcoin.org and bitcoind is running, but it is not syncing the blockchain. Users on reddit suggested, that there might be a problem with the firewall.

Which other ports except port 8333 do i need to forward to the VM?
Or is there another problem with my installation?

Output of bitcoin-cli getinfo:

 "version": 130000,
  "protocolversion": 70014,
  "walletversion": 130000,
  "balance": 0.00000000,
  "blocks": 0,
  "timeoffset": 0,
  "connections": 1,
  "proxy": "",
  "difficulty": 1,
  "testnet": false,
  "keypoololdest": 1474373107,
  "keypoolsize": 100,
  "paytxfee": 0.00000000,
  "relayfee": 0.00001000,
  "errors": ""

[achow101]

You need to allow both incoming and outgoing connections to and from port 8333

[Fr0stst0rm]

You are right the port is not open for outgoing connections.

I use a qemu hook to do the port forwarding.

Here is the important part of the qemu hook:

iptables -t nat -I PREROUTING -p tcp --dport 8333 -j DNAT --to $Guest5_ip:8333
iptables -I FORWARD -d $Guest5_ip/32 -p tcp -m state --state NEW -m tcp \
--dport 8333 -j ACCEPT

How do i open the port for outgoing connections?

[achow101]

How do i open the port for outgoing connections?

I'm not quite sure as I am not particularly familiar with iptables. I do know that it's something like

Code:

iptables -A OUTPUT ....

where the .... is stuff that I don't know. Try google, it's very helpful.