dan@upvote.au 11 months ago
For AdGuard Home, I’d recommend running it on two servers so that your internet doesn’t break when one of the servers is down (eg for maintenance, upgrades, etc). It runs well on a Raspberry Pi. You can use AdGuardHome-Sync to keep the config in sync between the two servers.
Dave@lemmy.nz 11 months ago
How do you get your DNS to point to the live one?
In my experience, the router’s primary DNS server is not used first, then the secondary. Rather your device just sends half of the requests to each. If you run two and one is down, every second request fails. Unless you can run a load balancer, but then you’re back to a single point of failure.
SciPiTie@iusearchlinux.fyi 11 months ago
The client does a fallback if one dns doesn’t answer. That’s why dns ad blockers fail if 8.8.8.8 or some other dns is added as a secondary :)
Dave@lemmy.nz 11 months ago
Hmm I’ve definitely see clients just say no when the first fails. How do they tell the router to try the other one? Does the router send both DNS servers to the client or does the client request a lookup from the router? Maybe my router sucks.
SciPiTie@iusearchlinux.fyi 11 months ago
The router is not directly involved in a dns query except, we’ll, the routing if it’s an non local IP. The DNS ip addresses is propagated either via dhcp together with the clients or directly configured in the client. That said: most routers serve as dhcp server at the same time. Perhaps your router is configured to always provide your ISPs DNS as primary.
How the client handles the decision which to query I honestly don’t know and I guess that’s why you and I made different experiences!
dan@upvote.au 11 months ago
If one of them fails, the client falls back to the other one. That’s the main reason why you can configure two.