Regarding PBS Datastore storage setup best practices

[justice41]

I currently am trying to figure out the best setup for PBS in my POC lab. Right now my PBS is running its datastore on an ISCSI remote NAS.
However I would like PBS to hold a local backup first before dumping the backup to NAS (since I know its working i'm planning two datastores: remote and local)

What would be the best storage setup for a local datastore in PBS? The easiest way I can do is hardware RAID 5 which is already built in in the Dell R620 that I am using.
Would there be any benefit in using ZFS? And if so are there any considerable performance difference between a flashed PERC card to IT mode vs installing an actual LSI HBA card? For hardware raid I can populate 8 x 2.4TB SAS drives in RAID5, for ZFS RAIDZ-1 with two SSD for ARC/ZIL cache? I am not sure about this as I have never tried it before.

Thanks a lot!

 

[VictorSTS]

ZFS will add bit rot protection and the chance to use ZFS special device [1]. ZIL cache will not help as it is only used with sync writes, which PBS does not do. Second level ARC may help, but in my workloads has had low impact and no longer use it.

On ZFS you can also set recordsize per dataset, so you can adapt that if needed. For PBS 128k usually works well. If at some point you want to test some recordsize you can create another PBS datastore on another dataset. On a RAID card you are stuck with whatever block size was set at RAID creation.

Don't know about that PERC controller, but I've seen issues with IT flashed cards becoming very slow due to the new firmware limiting the disk queue to very low values. Given the cost of boh flashing the card and getting an HBA you may try it by yourself.

[1] https://pbs.proxmox.com/docs/sysadmin.html#zfs-special-device