[c-nsp] 6500 IOS recommendation?

Chris Welti chris.welti at switch.ch
Tue Oct 22 08:13:01 EDT 2013

A little word of advice for those that use BGP: Don't use 15.1(1)SY and 15.1(1)SY1.
They have a nasty little BGP bug that can create black holes or loops
for random prefixes due to stale RIB entries of withdrawals that are not processed correctly (CSCuh43027).
Some withdrawn prefixes are being removed from the BGP table, but not from the RIB!
It's very hard to debug and even notice as it usually only affects a couple thousand prefixes, but it's
A lot of 15.1, 15.2. and 15.3 trains have the same issues, so be careful also on the 7600 "S" train.
It is fixed in 15.1(2)SY and 15.2(4)S4 only.
So if you want to use 15.1 on Sup720/Sup2T, use 15.1(2)SY.


Am 10/21/13 8:44 PM, schrieb Phil Mayers:
> Jon Lewis <jlewis at lewis.org> wrote:
>> Are people actually upgrading to 15.1SSY, or just running late
>> 12.2(33)SXI 
>> or SXJ until these boxes run out of resources?
> We're on sy1 everywhere, seems fine. A couple of minor niggles, no worse than any average sx release.

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