CBS250 Port Flapping 3.1.1.7 Unifi AP and Poly Phone

[jdavidson1604]

We are getting an issue that started yesterday at 2 different sites with similar but different topology. We have tried the following items in stages and cannot seem to get a resolution.

CBS250-8P-E-2G

Current FW 3.1.1.7

Unifi AC-Lite is constantly disconnecting at 1 site

Unifi Ac-Pro is constantly disconnecting at another site.

We have over 30 of these deployed and only having issues at these 2 sites and both issues started yesterday.

We also have 1 VoIP Polycom phone disconnecting randomly as well at the second site.

Attempted fixes that were recommended by TAC and cisco forums.

Smartport we already had disabled from previous known issue. - we didn’t find this to still be on in SSH despite it being off in GUI

CDP disabled

Disabled STP (Spanning Tree)

Changed POE to Port Limit

Moved AP to another Port

We tried Disabled EEE energy saving

Rebooted the switch

Rolled AP back to previous firmware version

When the gi7 Port goes down we are losing POE and the AP is rebooting. So this is not just a log issue, we are experiencing actual onsite issues.

Any thoughts?

We do use Auto Voice VLAN with LLDP but we even tried turning that off and no luck. 

[jdavidson1604]

Update from Cisco support, they have validated that it is an issue isolated to the 8 Port version, but they are unable to determine at this time what is causing it and it is being escalated Monday after the US closure ends, hoping for an update early next week.

In the meantime due to constant reboots I have tried to rollback to oldest known firmware 3.0.0.61. It is too soon to tell, but looking hopeful 1 hour in with no issues.

[jdavidson1604]

Update after 2 hours of running 3.0.0.61 we got several flaps with confirmed POE disconnects. I am still on 3.0.0.61 for testing and I turned EEE back off, so far 2 hours with no issues and will continue to monitor.

[jdavidson1604]

So after 14 hours I thought we weee good but the flapping has returned. I continue to have APs rebooting at 2 locations and some phones. Does T look like there is anything I can do until Cisco gets back to us.