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SG220-26 switch intermittently drops LACP groups

tsp
Beginner
Beginner

Hi - was wondering if anyone else has seen this problem - recently installed two SG220-26 switches; 4 separate LACP port channel groups were configured - 

#1 - 2 port LACP port channel group to a second SG220-26

#2 - 4 port LACP port channel group to a Windows 2012 R2 Hyper-V Server virtual switch

#3 - 2 port LACP port channel group to a Windows 2008 R2 server (backup server)

#4 - 2 port LACP port channel group to a Windows 2008 file server

The switch firmware is up to date (1.0.0.19), as are all of the NIC firmware and drivers.


Periodically, all of the Port-Channel groups go down and I see the following logged -

Notice  Port-Channel1 link down

Notice  Port-Channel1 STP port state is set to Disabled

This is repeated for the other three Port channel groups.  Around 20 minutes later, they all come up again -

Notice - Port-Channel1 link up

Notice - Port-Channel1 STP port state is set to Blocking

Notice - Port-Channel1 STP port state is set to Learning

Notice - Port-Channel1 STP port state is set to Forwarding

Again, this is repeated for the other three Port channel groups.  

This happened last night 4/21 at around 10:30 PM, and before that, on 4/17 at 10:10 AM for about 20 minutes

All of the other ports on the switch appear to be okay and working fine when this happens, it's just the port channel groups that are exhibiting this behavior.  There are no other errors in the logs indicating what's going on.  We've been fortunate so far in that this is happening off hours or on weekends, but it's very annoying because these 2 SG220-26 switches were replacements for a single SG220-50 purchased in December 2015 that was very unstable and Cisco was never able to figure out what was going on.  I also checked to see if this was a possible load issue (e.g. backups running) but that hasn't been the case - this has happened during times of minimal network activity.

Any thoughts?

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