Good solution to automatically revert to "normal" if Pi Hole dies?


Thanks for the explanation.
I think this is both exactly what I am looking for and not looking for at the same time.
The reason being maintenance of 2 Pi-Hole, and stat gathering / analysis. Specifically thinking of needing to whitelist a domain…I’d not know which Pi-Hole served the DNS request?
In terms of DHCP leases, are they dished out in numerical order? So if pihole1 is set to use range 50-150, would that prioritise over pihole2 at 101-250 for example? I thought not?



Thanks also for this.
Makes much more sense to me now and I may try and run in this manor, as well as how @jfb explained below to see which best suits my needs.
I think a power pack is also need on at least one pi, in case of a power outage.
Any recommendations?



I run two Pi-Holes in parallel, with the router providing DHCP. I find that in my network (Apple routers), that clients tend to stay on the first DNS provided to them by the router. The only time they jump is when that Pi-Hole is down, and then they move back when it’s up again. So, I just look in that Pi-Hole if something needs to be listed.

I don’t know. However, I am sure you are up to an experiment. Try both setups, see which works best for you, and let us know the advantages/disadvantages of each.



In my case I run a 1h lease time (lots of traffic on my network with new devices and monitors for new leases).

I am running all important devices on a couple of APC UPS’ that provide me roughly 4 hours of juice (each)during a power outage.



I have two Pi-3B+ with an 8 port switch, router and modem on a decent sized home/small office UPS) (maybe 650 VA?). This will run those devices for a few hours during a power loss.

For the Pi alone, you can get a battery backup hat that’s pretty nice. It doesn’t keep the Pi running, but it gracefully shuts it down. With my UPS, the Pi doesn’t shut itself down as the UPS nears exhaustion.



Part of my ‘problem’ is my router is very locked down by my isp, so I can’t manually configure the DNS server on the router. Most annoying.

I admire your optimism in my ability :joy:

I also run a 1 hour lease time, but traffic in my network is, I would say in comparison to others, minimal, maximum 20 devices at any one time, normally lower and very few ‘new’ devices.
Interested in how you monitor for new leases though?



That deviates this topic from it’s intended purpose.

I can share that too.

It involves dnsmasq and push notifications.



Fair one, feel free to drop me a message