VM Storage
Proxmox presents an interesting challenge when it comes to managing bulk storage. Over the years, I have tested several ways of dealing with this.
Pass the whole honkin' drive through
Proxmox allows you to passthrough a block device into the VM. Issue is, this is a one to one relation; that is to say, only one of your VMs can access the disk(s) you choose. Of course, you could then share the disks via a network protocol and mount them on other VM guests, but there's a better solution below.
Also, from a data integrity standpoint, I have some reservations as to adding another layer of translation between your I/O requests and the drive controller. If the data were to be corrupted somehow during translation, you're in for a bad time, even with software raid (your raid software is nonethewiser to errors)
Pass through a PCIE HBA card with drives attached
This is similar to the previous method, however you are passing a drive adapter card into the VM. This would avoid the I/O translation issue, as the VM gets direct memory access to the PCIE drive adapter, and therefore is able to speak to it directly. However, there is the same downside which is only a single VM has access to your drive(s).
Use a network based protocol
If we have the drives mounted on the host, and the host shares a network with a VM, how about we share "over the network" and mount the drive on the guest? This is the solution that I went with on many installations.
- Create a private bridge network that is not attached to any NICs and assign the host an IP to use on the bridge
- Create a network interface for each VM and connect it to the bridge
- Assign an IP to the interface and mount the network share via the hosts' IP
If you use ZFS, an easy way of sharing a dataset is by settimg the sharenfs property, which will automatically manage a zfs share for you. For example,
This option is pretty neat, as it allows multiple hosts to access one or more mount points from the host. There are some strange