Hi,

Am 25.05.11 12:48, schrieb Simon Annear:

At least I can spot an error here:

> Here is the output of utquery on my sunray
> 
> 
> me@sunray29:/opt/SUNWut/sbin$ ./utquery 192.168.0.199
> terminalID=080020f94a6a
>     terminalIPA=192.168.0.199
>     model=CoronaP2
>     currentAuth=192.168.0.29
>     currentFW=4.3_50_2011.04.22.22.07
>     currentBarrier=430
>     currentBarrierLevel=430
>     currentMTU=1472
>     currentLease=5791
>     Subnet=255.255.255.0
>     Router=192.168.0.210
>     MTU=1472

The MTU of 1472 is definitely wrong here. You most probably followed the
following guide to find your optimal MTU settings:

http://blogs.oracle.com/ThinkThin/entry/the_importance_of_mtu

However, the author there was slightly wrong and suggested to simply use
the ping command and increase the buffer size until fragmentation of
packets occur. That's why you most probably have set 1472 here.

But the buffer size you usually specify with the ping command is without
including the header size of the IP packet itself. So to correctly
identify your maximum MTU size you need to add 28 bytes to the value you
found being the one that was transferred without getting fragmented.
Thus, if you used the ping command and identified 1472 bytes to be
transferred without getting fragmented you need to add 28 bytes and you
have to set 1500 for your MTU. Therefore you should set your MTU to 1500
in the DHCP settings that get send to your sunrays.

best regards,
jens
-- 
Dr. Jens Langner                                     Ph: +49-351-2602757
Helmholtz-Zentrum Dresden-Rossendorf
Institute of Radiopharmacy - PET Center                [email protected]
Germany                                              http://www.hzdr.de/
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