3 node HPE MSA backed cluster - want to install PBS on Synology - will that work?

[mpotoka]

Migrating from a 2-node ESXI/SAN setup using Veeam for backup to Synology/Wasabi

I have 1 new Proxmox node currently connected to the SAN (SAS cables) multipath setup etc. I have started migrating a couple VMs as POC so now planning full migration.

I was considering installing PBS on my Synology so it is not part of the cluster for recovery purposes - but the Synology does not have direct access to the SAN. Is that an issue?

I will have a 10G network setup between the synology + Proxmox nodes

 

[Johannes S]

The pbs doesn't need to be part of the cluster so as long as he can access the storage on the NAS you should be fine.

 

[zandhaas]

I, a home user with the small proxmox nodes, on mini-pc's have installed the PBS server as a VM on my synology NAS. And everything is working perfect.

https://www.reddit.com/r/Proxmox/comments/1ejcosy/pbs_on_synology_ds1621xs/

 

[mpotoka]

The pbs doesn't need to be part of the cluster so as long as he can access the storage on the NAS you should be fine.

To clarify - PBS would be able to access the NAS for storing the backups, but it would not be able to access the SAN, which is corrected directly via SAS cables to the 3 HPE servers.

Maybe what I'm getting at is does PBS only need to communicate directly with the PVE host which is sort of functioning like a proxy?

 

[waltar]

That would work as the msa provide virtual disk through your sas cables to your pve nodes as they would be internal real disks which pbs backup.

 

[Johannes S]

I'm not sure whether I understand you correctly or not. I understand that you are installing PBS as a vm on your NAS, ist this correct? Than you would add the NAS storage to the PBS vm and be good. The pbs needs to be reachable from PVE for backup and restore. If you want to sync your backups from your NAS-PBS to another PBS (Great idea for vor offsite backups e.g. on a cloud vserver or something like tuxis proxmox backup server cloud) the mirror PBS will also need access to it. As long as you don't want to use the SAS for backups the PBS doesn't need any connection to it. Or is your PBS on a custom server but will access the NAS via NFS or ISCSI? This should work but isn't supported officially since PBS writes and reads a lot of small files ("chunks") for it's advanced featureset (like deduplication) which performs better with local storage.
Another thing to consider: In your subject you write that you want to setup a three node cluster, in your op you wrote that you will start with one node and are planning to replace an existing two-node EXSI cluster. Please not that the documentation recommend having at least three voting members in the cluster to maintain high availability. So if you have three servers inside the cluster it's not an issue at all. If you however want to stick to a two-node-cluster you will need a so called qdevice to maintain a majority vote in case of a failed node: https://pve.proxmox.com/wiki/Cluster_Manager#_corosync_external_vote_support
This qdevice doesn't need to run on big hardware, even a raspberry PI would do. But since you already have a PBS in your architecture it's propably the easiest solution to add the PBS as qdevice. Please note, that this is only needed for two-node-clusters. In case of odd-number-clusters, e.g. with three regular nodes the manual recommends AGAINST installing a qdevice since it's actually more likely to reduce availability.