RESOLVED: Re: 8.1 Box does not react on ICMP "unreachable - need to frag"

[Artyom Viklenko]

18.01.2011 14:23, Axel Rau пишет:
>
> Am 18.01.2011 um 11:00 schrieb Axel Rau:
>
>> The DB server returns its query results successfully until an
>> oversized message is being sent (with "DF" set), which the GW2 refuses
>> with an ICMP "unreachable - need to frag (mtu 1492)
> I could convince the firewall to defragment the packet itself. (-;
> This was a pf issue (I mixed up option "set reassemble" and filteropt
> "fragment").
>
> I'm still looking for an answer to question 1:
>> 1. Shouldn't DB2 fragment and resend the packet?


Generally - yes.

Make sure DB2 got ICMP need-frag message and it not blocked.
Also, check sysctl variable 'net.inet.tcp.path_mtu_discovery'.

Hope this helps. :)



-- 
            Sincerely yours,
                             Artyom Viklenko.
-------------------------------------------------------
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