[CentOS] CentOS 6 - VM network bridge issue (SOLVED)

Wed Jul 20 08:24:44 UTC 2011
James Hogarth <james.hogarth at gmail.com>

>> Initial thought is a routing issue particularly with multiple NICs.
>> What does 'ip r s' reveal?
> That was it!  ip r s showed that I had the local facing NIC (eth1) as the gateway, which caused all outgoing packets to be routed to the local network DUH!.

Yup been there before.....

So long as the local NIC doesn't need to hit any other internal
subnets you'll be fine... otherwise don't forget to add the
appropriate RFC1918 static routes to go out that interface with the
default being the external one....

Also another thing to watch out for is asymmetric routing. If it is
possible to get to a destination via either interface and due to
routing issues elsewhere the packet does not return to the same
interface through the same gateway you can get odd behaviour.... In
which case you would need to set up policy routing rules to ensure
stuff enters/leaves the right way... but dont' worry about that for
now - just remember it for later if you get odd network behaviour....