I want to set up a redundant DNS based on Bind9, including failover for write operations. I have DHCP dynamically update DNS based on client hostnames, and I need this functionality to continue to work if the master DNS server goes down.
Right now it's set up as master/slave - which will block write operation if master goes down. This makes it quite tedious to do upgrades to the master node, as critical functionality will be down for the duration.
It seems Bind9 doesn't support multi-master natively, but it should be possible to do zone transfers and sync outside of bind.
Some ideas:
- Flip config from slave to master on failover
- DLZ database replication
What's a practical example of successfully doing this?