Limited hardware Proxmox setup. Need advice.

[davidvargas]

Hello,

I have a handful of baremetal servers that I would like to migrate to proxmox vms. As I move the data off the servers, I can reuse hardware to add to the proxmox cluster. Each server is currently configured in a raid 5 with 20 ish Terabytes available. All storage is using HDDs and there is no money available to upgrade to SSD or NVMe. To complicate things. There is only one free server currently and not a lot of storage to shuffle things around. Which means I can only really start out with one or two servers to start a cluster and have to expand from there as I free up devices. What are my best options to set up storage for this cluster? I need some level of failover and redundancy. At this point, it doesn't seem like I can do Ceph because you need 3 servers to get started and it looks like it needs faster hard drives as well.

 

[Guillaume Delanoy]

Hello,

RAID 5 is not the best choice to install a hypervisor on, because KVM processes will simultanously want to read/write on disks while the RAID controller would send each one of these requests to -at least- three disks, which would result in bad latency and poor performance.
If possible, I'd suggest you configure your RAID Controller to do RAID 1, so you get the expected failover and redundancy.

Then, set up on Ext4 or XFS (ZFS on RAID would make no sense).
Once you get to install a second server and maybe a third, I -again- would advise you *against* setting up a Ceph cluster on RAID controlled hardware, for the same reasons as below: you'd only get bad latency and poor performance from this.

Instead, setting up glusterFS shares may be a good move, and won't require you to wait until the third server is available before you get to use replication.

Hope this helps,

GD