Machines will be fine with just one primary DNS server. The main reason for running two is so that you still have one working DNS server if either machine goes down, for example during maintenance.
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mic_check_one_two@lemmy.dbzer0.com 1 day agoPi-hole. You’ll want to run two, because machines will use both a primary and a secondary server for their DNS requests. If you don’t want to buy a pair of raspberry pi’s, you can run it in Docker, which basically keeps it isolated to its own tiny virtual machine. So you’d just need to spin up a pair of docker containers to run the pair of pi-holes. If you’re using Docker, they’ll need a pair of volumes too, or else they’ll lose all of their data every time they reboot.
You’ll want this to be on a machine that is running 24/7, because any time it shuts down, your internet will essentially stop working. That’s why lots of people end up just throwing a few raspberry pis in a closet and forgetting about them.
Once it’s installed, you’ll need to load it with block lists. The default ones are pretty basic. I’d just google something like “pihole blocklists” and figure it out from there. Each list will be a URL, which allows the pihole to pull updates, (which you can tell it to do via the built-in web UI).
chellomere@lemmy.world 1 day ago
Archer@lemmy.world 1 day ago
No point if you have a network in the 10.0.0.0/8 IP range. There is a bug where they will randomly stop serving DNS to IPs outside of their subnet
mic_check_one_two@lemmy.dbzer0.com 1 day ago
Unless I’m misunderstanding, that doesn’t sound like a bug at all. Outside of a few specific circumstances, devices shouldn’t communicate with anything outside of the given subnet mask. Rejecting traffic outside of that subnet mask is exactly what it should do. And why wouldn’t your pihole be in the same subnet (or at least be included in the subnet mask) for the LAN? You can have the pihole’s IP address be whatever you want, so give it an IP in the same subnet.
Archer@lemmy.world 1 day ago
I use VLANs and different subnets for security. Having PiHole break randomly every few weeks and seeing the config is different when I didn’t change it was beyond frustrating, so I just gave up
Vanilla_PuddinFudge@infosec.pub 1 day ago
Then change it?
1984@lemmy.today 1 day ago
Its actually not easy to run two of them since they are not designed for using a shared disk (you can get corrupted data). Its also not necessary, you can just leave the secondary dns server blank.
But if you want two because you want high availability in case one of your piholes goes down, you can rsync the settings between the two machines every 5 minutes or so. Its important to keep them in sync that way.
mic_check_one_two@lemmy.dbzer0.com 1 day ago
The secondary DNS isn’t for redundancy; machines will split requests across the two for load balancing. If you only have one running, you’ll end up with ads slipping through as the device still uses the default secondary DNS.