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This is a bit of a specific extension to this question.

I've got two ASA's that feed into a Procurve switch, and then into an IPS. All is well except that the procurve absolutely refuses to autonegotiate with the ASA's...The asa's run 100full, and the procurve autonegotiates to 100half. It does it for both ASA's, so it's probably not a failure on one of them, and everything works fine if I force the procurve to 100full.

Has anyone else seen this issue? I've been buying more HP hardware, but I'm not keen on getting equipment that's not going to play nice with my Cisco backbone.

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up vote 2 down vote accepted

I have a similar set up with ASAs and Procurves (but no IPS) and no problems with auto-negotiation. However, our equipment is connected at 1Gbps, not 100Mbps.

We did have problems between an HP switch and Cisco switch where both ran at 100 (and had to be set manually to 100/full).

My usual order of operations is:

  1. If >100mbps, use auto-negotiation. If it doesn't work, figure out what's broken, because it should work.
  2. If =100mbps and auto-negotiation is having problems, set manually to 100/full and forget about it.
  3. If <100mbps, throw it away =)
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I have seen this a number of times and not just with Cisco and HP. We have a wireless radio and a Cisco box that will not auto negotiate. It should work but just does not. Basically, you have the fix... Set the speed and duplex on both the same and away you go.

It usually seems to be hardware that is somewhat static(servers, routers,etc) so it is set at each end manually and documented and then not an issue.

Not ideal but it works. It also seems to happen much less often than in the past.

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