I'm currently running HA on a Pi3... it works fine, but it's now a single point of failure.
I have some new hardware arriving to run VMs in and was intending to move HA to it, but now I'm wondering if I can have HA in 2 places for fault tolerance.
I'm aware that there's no built-in failover options, but has anyone done something similar?
Correct, OPs needs is describing what kubernetes was made for. Fault tolerant container orchestration. Or any other orchestration framework.
However it's a best to learn and get set up. Migrating all of my containers over took a couple of months of learning and trial and error. Each person has to decide is that level of effort worth it in a home application
I run HA as a container in a vm. I back HA data up nightly and the compose script for running HA is archived on github. If the vm dies there is another vm that can bring it back up. If the host dies (I have a pool of xenserver (xcp-ng) hosts, so it would be a major domestic disaster if they all croaked) I have a fallback to run HA on docker on wsl. If the house burns down all the scripts are on GitHub and the backups get sent to Azure monthly. I think I’m covered.
I don't have any zigbee devices at the moment, but I was looking into network based ones... not sure if I can have 2 of those? (Again, no zigbee expirence yet to know the options)
HA might be possible in a active passive configuration if you don't have any dependencies on external hardware like a zigbee stick. Active active would need support by HA and I don't think that is implemented.
I think the most secure thing is to keep regular backups so you can roll back easily.
Thanks, yes, I think active-active would be another magnitude harder... and would need database, history, etc on shared storage... over the top to jist ensure the lights stay on.
And backups are essential for all use cases (and not just the built-in HA backup left on the device / VM / container that just failed!)