I've had a 13.37 machine providing services ( squid, email, samba, etc. ) for a local network over the last year. No issues.
Just in the last week however, users started having problems connecting to some of these services. Specifically squid was an issue.
I spent hours troubleshooting this issue and finally realised that some of the services were only listening on their ipv6 address and not the ipv4 address. Grrrrr.
If you look at some of these services like apache and squid, their
listen statement simply uses the port number in which case, the service should bind to all addresses ( ipv4 and 6 ). Well that is the expected behaviour. I had restarted the server to make sure it wasn't a temp problem and even after the restart, the problem continued. In this case, the service was only binding to the ipv6 address. I added
blacklist ipv6 to /etc/modprobe.d/blacklist and also now use:
0.0.0.0:<port>
for the problematic service which should forcefully bind it to the ipv4 address.
So my question is does anyone know why this would have started to be a problem all of a sudden? No changes have happened on the network except for a recent upgrade of our firewall system ( separate from this services machine ).
