Panic during boot (in_arpinput).

[Robert Watson]

On Wed, 15 Nov 2006, Ian FREISLICH wrote:

> Robert Watson wrote:
>> On Wed, 15 Nov 2006, Ian FREISLICH wrote:
>>
>>> Ian FREISLICH wrote:
>>>>
>>>> I have 2 servers each with 255 vlan interfaces and carp interfaces in 
>>>> each vlan.During the boot up while it's configuring the interfaces, it 
>>>> reliably panics.  It boots fine if no network cables are plugged in (and 
>>>> in the test evironment on a quient lan).
>>>>
>>>> It's an SMP machine.  My guess (from the panic message below) is that an 
>>>> arp query arives on an interface it's in the middle of creating or 
>>>> something like that (highly unsophisticated debugging conjecture).
>>>>
>>>> In the mean time I'm going to try a UP kernel and see if that masks the 
>>>> problem.
>>>
>>> FWIW, a UP kernel has the same problem.
>>
>> What happens if you disable PREEMPTION on UP and try the same thing again?
>
> Same thing.
>
> If I don't assign the carp interfaces a vhid and pass at boot time, it boots 
> up OK, but I need the carp interfaces.  I can arrange serial console access. 
> I have a similar system from ~"Tue Aug 29 09:47:50 SAST 2006" that works, 
> but I suspect it may suffer the same problem.  I'm about to test this.

This suggests that it is not the race I was worried it was, which is really 
good news :-).  This makes me suspect a CARP-specific bug as opposed to the 
wider issue of under-synchronization of the address lists.

Robert N M Watson
Computer Laboratory
University of Cambridge