Hello everyone,

first time ever posting on lemmy, feels good 😉

I have a question regarding DHCP in my local network.

My current setup is as follows:

  • DHCP provided by router (Fritz!Box 7490)
  • DNS provided by pi-hole hosted on a raspberry pi
  • DHCP pushes the IP of the raspberry via DHCP to all clients

My problem is: When the raspberry pi (running pi hole) is down for any reason, none of my devices has internet access anymore. This is due to the fact that the Fritz!Box router (aka DHCP server) has no option to push a secondary DNS as a fallback to its clients.

One option would be to buy another router which has the option to push a secondary DNS, which I would prefer to avoid, since otherwise I am happy with the Fritz!Box.

So I am looking for alternative configurations with my existing hardware. I could for example use pi holes DHCP. Or I could use the DHCP server package of a synology NAS which is also part of my local network. Or is there another option, maybe using some DHCP service on the raspberry pi or in a docker container or something like that? Does anyone have experience with one of these setups and can tell me if it is possible to provide the clients with two (prioritized) DNS options? What would you recommend? Thanks!

  • @[email protected]
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    41 year ago

    Keepalived (or similar CARP or VRRP virtual IP system) would allow you to run 2 piholes that share the same virtual IP.
    If the main goes down, the backup will take over the virtual IP

    • The_Pete
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      51 year ago

      Lol, this is peak selfhosted. The obvious solution is to get a router/DHCP server that is normal enough to push out two DNS servers.

      The selfhosted way is to set of keep alived or a load balancer, because why the fuck not.

    • nsaobserverbot
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      31 year ago

      Nice, but you don’t need this per se. If you have two Piholes doing DNS, one of them can do DHCP and push the two pihole DNS server addresses. If the one with DHCP goes down temporarily you will not get a new addresses, but DNS resolution continues one the one running.