[CentOS] Networking just stopped working

[Christopher Chan]

> Did not know that both had stopped. Conflicting IP addresses was just a
> suggestion.  May not be the problem at all.  With bonding, breaking one
> might break both down at the MAC level ...
>
> Hmmm ... which bond mode are you using?

Why mode 4 of course.

>
>> The box with the problem just so happens to be the only box using
>> bonding, 802.1q and a four port Qlogic Netxen NIC. I think the
>> chances of there being a problem between these three more likely than
>> some 'ghost' boxes getting assigned the same ip addresses when I am
>> the only admin around.
>
> If you are the only admin, then its not that likely.  Then again, I once
> had a power spike reset a wireless router on my network without me
> knowing.  Default settings were close by not quite right, and it took me
> a couple of days to track down the problem :-(

Too bad there are no defaults that use the subnet assigned to the school 
or the 192.168.0.0/16 (no, not my idea - inherited)


>
> If it was working, then suddenly stops, then something must have
> changed.  I gather you have some configuration and change management
> system in place?  Backups of conf files?
>

Hahaha, that was the best part. It just stopped. And stayed that way too 
after a reboot, reboot of switches and only started working again when I 
ran tcpdump for some reason.

But another colleague did find this in the iLo report:

Repaired Network 07/06/2010 12:35 07/06/2010 12:00 2 Network Adapters 
Redundancy Reduced (Slot 10, Port 3)

Repaired Network 07/06/2010 12:35 07/06/2010 12:00 2 Network Adapters 
Redundancy Reduced (Slot 10, Port 4)

Repaired Network 07/06/2010 12:35 07/06/2010 12:00 2 Network Adapters 
Redundancy Reduced (Slot 10, Port 1)

Repaired Network 07/06/2010 12:01 07/06/2010 12:00 1 Network Adapter 
Link Down (Slot 10, Port 2)

Time to ask the HP chap what this is all about.