[PVE-User] Cluster network via directly connected interfaces?

[Stefan M. Radman]

You might want to have a look at
https://pve.proxmox.com/wiki/Full_Mesh_Network_for_Ceph_Server
This is what (I think) Thomas Lamprecht is referring to and it should also be usable for corosync.

The advantage of this configuration over the bridged solution used by Uwe Sauter is the zero convergence time of the topology.
A bridged solution using the standard Linux bridge might break your corosync ring for a long time (20-50 seconds) during STP state transitions.

Disclaimer: I have tried neither of the two solutions.

Cheers
Stefan