strange TCP issue on RELENG_7

[Kip Macy]

On Sat, Aug 23, 2008 at 10:52 PM, Julian Elischer <julian at elischer.org> wrote:
> Mike Tancsa wrote:
>>
>> At 10:16 PM 8/23/2008, Kip Macy wrote:
>>>
>>> Can you help me out a bit with your workload?
>>>
>>> tcp_offload_connect(...) needs to determine which interface an address
>>> corresponds to see if that interface supports TCP offload. The code
>>> does the exact same thing as ip_output does except it doesn't have the
>>> inpcb locked (which isn't used as part of the route lookup).
>>
>> This is the only RELENG_7 box that I have where it routes tcp packets
>> asymmetrically, so that sounds like it might be the portion that is badly
>> interacting. The server has just one default gateway, which is out em0, but
>> clients all over the net will connect to IP addresses aliased on lo0 and to
>> the one IP on em1.  But all connections exit out em0 other than connected
>> routes of course.
>>
>>        ---Mike
>>
>>> Julian has worked in this code most recently, maybe he has some idea
>>> what is going on.
>>>
>
> huh? wha?  I haven't been following this thread.. what's up?
>
Julian - see previous e-mails, the arp cache gets messed up as a
result of calling rtalloc in tcp_offload.c - which is done to
determine which interface will be used for connection. Any thoughts on
why it may end up with dozens of bogus entries?

-Kip