CIST starved for a BPDU Rx

[nigel hird]

I have an HP5406 switch, connected to 3 floors. On each floor, I have two seperate connections going back to the HP5406. Each floor has about 7 x HP2520POE switches, with a connection from the HP5406 going to the top HP2520 switch, and also the bottom switch HP2520 switch, and these switches are then "daisy chained" connected via ports 23 and 24. Same scenario on each floor. All switches have spanning tree enabled. All the vlans are created in the 5406 switch, then tagged through to whichever switch it is required. We are running VoiP in this scenario.

Now, on monday the data circuit between the HP5406 switch and the main core switch at central HQ went down. The telecoms guys say that voice calls should still be able to be made within this remote site, but on checking the config of the 5406, all the vlans were disabled when the link went down, meaning obviously the Voip phones swent down. There is an error message which says:- "CIST starved for a BPDU Rx on port B24 (link to HQ) and also "CST Root changed from 32768:000883-918b00 to 32768:002561-5bec00."

Is this a spanning tree issue, and should the vlans still be enabled even when the link back to HQ goes down? Loop protect is also enabled on all switches.

P.S. This thread has been moevd from Switches, Hubs, Modems (Legacy ITRC forum) to ProCurve / ProVision-Based. - Hp Forum Moderator

[Richard Brodie_1]

The error messages look fairly normal.

CIST starved for a BPDU Rx on port B24 -> I've stopped seeing root announcements.

CST Root changed from 32768:000883-918b00 to 32768:002561-5bec00 -> I've elected a new root with MAC address 002561-5bec00.

If you lose the root, things are likely to get messy until the reconfiguration has propagated through the network. I wouldn't be surprised if it took 20s or so.