Could anyone explain the behavior of DNS slave?
I am testing DNS server, for internal purpose, and after configuring master slave everything works fine, but I am willing to understand the mechanism behind,
Lets say,
dnsmaster.net and dnsslave.net [my 2 DNS]
However, I wanted to make dnsslave to be available to serve query if dnsmaster.net is down. [well it works until now]
Having said that, I want to update records on dnsslave.net [while dnsmaster.net is down].
I can resolve things from DNS slave but turning off master and updating records, but not until I restart dnsslave.net.
So, is this something caused by, expiry time on soa?
43200 ; refresh (12 hours)
900 ; retry (15 minutes)
1209600 ; expire (2 weeks)
300 ; minimum (5 minutes)
EDIT: I know what is the purpose of DNS master and slave, I am talking while dnsmaster is down, slave is only in use and I need to update A
record. [at this condition DNS doesn't work with reload it only works on restart, so anyone with better knowledge and experience please share your view.]
You cannot update a BIND slave by manually editing its zone file. Having said that, if you choose to use PowerDNS in a master-master setup, you can then edit the second server using PowerAdmin or manually editing the MySQL database (if database replication is configured).
Slave nameserver updates its data from master by zone transfer. When master is down, slave can only serve what it transferred from master earlier.