Re: MISC Large ICMP Packet

[Chris Hobbs <chobbs () silvervalley k12 ca us>]

Both you and Valdis nailed it - from hostmgr.uiuc.edu:

-----
This is hostmgr () uiuc edu.  I checked around and found out that
vacuum.cso.uiuc.edu is running our list-serv software.  I also
found out by default, AIX 4.3.x uses large ICMP packets to do 
some sort of MTU discovery on remote networks.  When it becomes 
a problem, it can be easily disabled, which our system admin has
now done on vacuum.
-----

Kudos to them for a really fast repsonse - 45 minutes from the time I
sent the first e-mail :)

Opus wrote:
> This is most likely an AIX box which by default has MTU discovery enabled
> used to discover what size of packets it can send.  This can be sdisabled
> on the AIX box with the following command.  This is not intended to be
> malicious.
>
> no -o tcp_pmtu_discover=0

-- 
Chris Hobbs       Silver Valley Unified School District
Head geek:              Technology Services Coordinator
webmaster:   http://www.silvervalley.k12.ca.us/~chobbs/
postmaster:               chobbs () silvervalley k12 ca us

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