How to promote slave dns to master dns

[ly.chea]

Dear all,

Currently I have 2 dns using bind on Debian v8 to run as dns server. One dns runs as master, and another one runs as slave. Slave dns gets record update from Master dns by doing the zone transfer, and those records are binary.

Now Master dns got issue, and I need to promote Slave dns to be master. Can you guide me how to do it?

Thanks,
Ly

[GarryRicketson]

No, I can't , how ever there are some good guides available, you can read them, and after that if there is something you don't understand, maybe somebody here would be willing and have time to try to explain.

On Debian servers , How to promote slave dns to master dns

This one is pretty good, it includes for Debian:
https://www.garron.me/en/go2linux/how-s ... -bind.html

You also might want to read this , from a mailing list:
https://lists.isc.org/pipermail/bind-us ... 93899.html

But why have just a single master? If you're worried about the primary going down, just have a warm standby ready to go. To keep zone data in sync, you could use shared storage, a replicated database (BIND does support a database backend), or perhaps some sort of also-notify
configuration. To do the failover itself, you could use something like
Pacemaker/Corosync, ucarp, or similar. Just pass a VIP back/forth between
the two -- your NS records would only use the VIP.

***The big issue I see with converting a slave to a master is that you'd have to change all of your zone definitions, change your named.conf and do so under time pressure. Then, when the master came back online, you'd have to change your zone definitions again. With config management software, not that hard to do, but servers are cheap these days -- easier just to create a failover pair (or group) for your master, then stand up as many slaves (doing update forwarding) as you need. If you purchase a DNS appliance (Infoblox, SolidServer, Bluecat, etc.), this is how they handle things.

This might be use full to you as well, it helps explain how to edit your
"named.conf" file, and is more Debian specific,...
https://wiki.debian.org/Bind9