====== Proxmox Cluster Trouble Shooting ======


===== Restart Cluster Node Registration =====

<file bash>
systemctl stop corosync.service 
systemctl stop pve-cluster.service
systemctl stop pvedaemon.service
systemctl stop pveproxy.service
 
systemctl start corosync.service 
systemctl start pve-cluster.service
systemctl start pvedaemon.service
systemctl start pveproxy.service
</file>

===== TCP Dump Multicast Cluster Traffic=====
<file>
tcpdump -n -i eth1 multicast | grep 5404
</file>

===== Print (to console) Corosync Log =====
<file>
journalctl | grep corosync
</file>

===== Print corosync Service Status =====
<file>
systemctl status corosync.service
</file>

===== Force Quorum =====
<file>
pvecm expected 1
</file>

===== Edit /etc/pve when cluster is down =====
<file>
systemctl stop pve-cluster
pmxcfs -l 
</file>
  * edit files, then run
<file>
killall mcxcfs
systemctl start pve-cluster
</file>

===== A note about Multicast Traffic =====
  * corosync and Proxmox clustering need multicast traffic to be configured properly for cluster nodes to see each other.
  * If a node keeps losing contact with other members make sure IGMP snooping is turned off at the switch and layer 2 level.
  * If some nodes connect initially then disconnect after a few minutes take a look at the multicast configuration of the switches these nodes connect through.