Proxmox cluster and STP on Unifi


New Member
May 13, 2023

I have a proxmox cluster with three nodes.
Each node has two NICs.

So, for each node, I have two interfaces (each on its own vlan) and two bridges:
vmbr0 - corosync, admin
vmbr1 - VMs

Periodically two of my nodes get rebooted at different times. After (a lot of) investigation, I found out that the Unifi switch is STP blocking ports of my nodes and, I believe, this is triggering the node reboot, since it can't communicate with the cluster.

What am I doing wrong? How can I prevent the switch from STP blocking the ports and triggering a reboot? What other info would be needed to investigate the issue?

Thanks. The bridges have STP disabled, but I'll disable STP on each port the nodes are connected to the switch and monitor.


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