Strange IPSEC activity over UUNet..

Craig Holland cholland at
Fri May 25 18:01:24 UTC 2001

-Typed after no sleep...bear with me please-

We use an IPSEC client for remote access to certain resources. I typically
use a Ricochet modem at home, but a lot us use IPASS for general ISP dialup.
Over the last week, I've been getting a lot of calls from people saying they
had problems connecting to the remote access server, but I didn't seem to
have any problems.  Then a couple of days ago, my Ricochet connection
stopped working.  The only common denominator is any connection that passes
through UUNet/AlterNet doesn't work.  Crazy? I dialup to a Telia pop, no
problem.  I dial up to a WorldCom POP, no problem. I connect with a Ricochet
(which goes through UUNet in this case)...broken. I dialup to a UUNet
pop...broken.  I don't get it.

The client reports that it is receiving fragmented packets, and that it
doesn't have the other fragment in its cache.  Its almost like the packets
are getting fragmented, and then some of those fragments are getting lost.
Because of how the client works, this breaks its ability to connect.

I've checked all my MTUs and circuits. I've reduced my MTU on the client to
attempt to stop this from happening. I'm running clean as far as I can tell,
and the good connections through other ISPs tells me my system is working
OK.  I've pinged my host from the destination network with large packets and
don't lose any.  Does anyone have any idea what this might be about?  If
this is rediculous...Great!  Just want to get a fix for this or find out
what is causing this.  Can someone from UUNet say if you are doing some
maint. that would cause this kind of activity?


Craig Holland
Network Engineer
Y!Messenger: cholland
Ph: (408)349-3572
Fx: (408)349-3707

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