The DNS records updated in GUI doesn't reflect in zone file quickly and takes around 30 mins to get updated. Are there firewalls between the master and slave servers?It sounds as though notifications from master to slaves are not working and so it's falling back to slaves polling the master.
Refer to the BIND 9 Administrator Reference Manual referenced in Section 16.7.1, “Installed Documentation” and the Specifies the hosts that are allowed to dynamically update information in their zone.
The default is to deny all dynamic update requests.
What, how, and where logging takes place can be extensively configured in BIND.
Normally, the default settings should be sufficient.
Nor can I use my email because it requires addresses that are in the primary zones!
I need to have the primary DNS re-transfer all the domains to the slave DNS.
This could be down to a firewall not allowing the notifications through but allowing the polling?
You need to debug why notifications are not working (if not firewall reason).
This file is not required for a slave, because this data is fetched from another name server.
To differentiate master and slave files, use the directory This option controls external write access, which would allow clients to make a DNS entry—something not normally desirable for security reasons.
I have modified the serial numbers in all the *.hosts files in the named directory.