I have 15 clusters of 3 x 3550's and 3 x 4506's with port-security configured on all access ports. Every day I experience random pot lockouts, on again random switches due to err-disable. Reason, switch seen MAC address 5258.5f55.55.c5 or address e8be.5bd3.5558 on port? The times indicate that this happens when clients either logon or logoff. We have update all drivers on the clients which are a mix of Dell's and Compaq's. Anyone came across this behaviour before? Port config attached.
Check to see if the ports are seeing any errors. We had a bug in 3550s(CSCef15178) due to which MAC Learning would Occur on Frames with Bad CRC and lead to port-security violations. This is a hardware limitation not fixed in any IOS but there are couple workarounds you could use.
1) switchport port-security violation protect
2)switchport port-security violation restrict
on the secure ports. Then the ports would not shut down when they receive a garbled packet.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...