[CentOS] A bridge problem

On 06/13/2011 11:02 AM, m.roth at 5-cent.us wrote:
> We just went to replace the bridge/firewall services one one server with
> the same on another. It's pretty simple, and I literally cloned (w/ rsync)
> a third server that does this onto the one that will be the new one. Then
> copied the /etc/sysconfig/iptables from the one being replaced, and
> brought it up this morning.

Specifically what did you rsync?  If you copied the ifcfg files, you 
probably need to adjust the HWADDR in each.  If you didn't get all of 
/etc, you might need sysctl.conf.  I'm guessing that's the case, given 
the symptoms and the fact that you had to also copy the iptables file.

> ifcfg-eth0
>
> DEVICE=eth0
> BRIDGE=br3
> BOOTPROTO=dhcp
> HWADDR=aa:bb:cc:dd:ee:ff
> ONBOOT=yes

There should not be a BOOTPROTO in this file.

> ifcfg-br3
>
> DEVICE=br3
> ONBOOT=yes
> TYPE=Bridge
> BOOTPROTO=static
> IPADDR=<our ip>
> NETMASK=255.255.254.0
> NETWORK=<our nw>
> GATEWAY=<our gw>

You don't need NETWORK here.

It would also be helpful to see the contents of /etc/sysctl.conf or the 
output of:

# cat /proc/sys/net/ipv4/ip_forward
# cat /proc/sys/net/bridge/bridge-nf-call-*
# brctl show