I am doing some testing with 2 UNRAID servers and a VM. We have a clunky database software that we can not take a real time snapshot of natively. In my testing I have a VM with 2 extra virtual drives, 1 of them is located on the NFS share. A software RAID between the 2 VM drives through a dedicated 10G network(if testing will upgrade to a infiniband). I know this is not how it should be done ideally, but the software is a PITA.
The goal of all this, is if one server goes down I can boot up a backup VM referencing the database VM drive quickly. We have offsite backups, and nightly snapshots as far as real backups go. So far testing of the database is working great. The downside is if I try to break it, it breaks hard. If main server goes down, the VM drive on the secondary works fine, I can reference it no problem. If I take down the secondary server the main server becomes unresponsive I think because of the lost NFS drive. If I try to unmount it, it fails. If I try to reboot the main server it will not reboot, the web interface still works but ignores any request/command you type in. Basically if the backup server goes down it takes the main server with it.
Is there a FAQ, or guide for this type of use case. Something I can do/implement to fortify the main server in the case of the secondary server dropping? Is there a unraid setup for replication across 2 servers that would support VMs?