A daily switch lockup, same time every day

[kevets]

Well, I am hoping this is the fix:

I had IP IGMP on a few VLANS and on the default VLAN, it had no IP Address. I believe my firewall got in the IGMP querier conversation and broadcast from my management VLAN to my default VLAN.

It seems that IGMP multicast can really screw up STP.

At any rate, removing all IP IGMP from my edge switchse has resolved the problem. After a few days, I'll announce victory.

[kevets · Accepted solution]

Well, to bring closure to this and hopefully help someone, even at the risk of personal embarrasment.

The main problem was HP800's with Intel NICS and old drivers, with IPv6 enabled. These NICs caused a staggering IPv6 neighbor discovery storm when going from sleep to wake.

Fixes include:

• getting rid of IPv6 -- we don't need it and it should have never been enabled
• updating the drivers
• configuring the ProCurve's with MLD protection

The "same time every day" should have been the clue I needed. And I should have wiresharked long ago, as the problem was immediately apparent from a capture (more than a million packets in a 1 second capture).