[CentOS] Networking Issue

Tue Jun 9 01:38:57 UTC 2009
nate <centos at linuxpowered.net>

Joseph L. Casale wrote:

> Now it seems there is still one last hurdle, when the connection is yanked
> to simulate a complete outage, asterisk still goes down. I can only assume
> this happens now as a result of no default gateway?

check the logs? run strace on the process? run tcpdump on
the interface(s) to see what traffic it is trying to transmit?

>
> Would setting up a silly route for 0.0.0.0/0 to say 127.0.0.1 for the
> internal
> nic in /etc/sysconfig/network-scripts/route-eth1 with a metric higher than
> what the ISP's dhcp servers default gw would be possibly cure this? My hope
> is that when the wan nic goes down, a route is still available.

Last I checked the 'metric' number in the linux routing table is
really only used when your using a routing daemon. as far as
default routes go, it should not have any impact.

I suspect the route is not the issue, I suspect that the app is
trying to talk to something external and then fails, it will fail
the same if you try to point it to a router that goes nowhere.

tcpdump should be able to tell you who the host is trying to talk
to. strace might reveal why.

nate