rrd error

I'm getting the error below after something happened (it was not happening before) and not sure that I changed anything deliberately. It prevent the status graphs (rrd, right?) to be displayed on the PBS administration section. Oct 11 22:07:17 pbs3 systemd[1]: Starting...

Hello, Today our cluster lost synchronization. Most of the nodes were shown as offline or unknown. The nodes were up but every node could see only itself and few other nodes. Restarting the pve-cluster and corosync didn't help so we brought everything down and started them one by one. For most...