Hi All,
We recently had an issue with primary DNS server (top-level domain). As part of our quarterly maintainance, the primary DNS servers was patched and rebooted. During the reboot windows, we have had users who complained of DNS queries failing and application being un-available. These applications are published via Citrix and hence the essentially of DNS being available for these apps to be launched.
Summary:
We have 2 DNS servers on our root domain. All the clients have the primary DNS server say 192.168.1.1 as its preferred primary DNS server on it's IP settings and the secondary DNS server 192.168.1.2 as secondary. Now, ideally during the reboot of the primary server, the clients should have it's DNS queries forwarded to secondary after it times out on the primary server. Seems like that didn't happen.
Is there a way to re-produce the issue on a test env without an actual reboot? Say manually, change the primary DNS IP on the client TCP settings to a non-existent address.
How to find when a DC is ready to serve DNS queries after reboot.? Netlogon services?
We also have a secondary UNIX zone on our Windows DNS servers. Most of the shouts came from this zone. Not really sure how Infoblox would handle the switch during the un-availability of the primary DNS server
How Windows DNS server will handle DNS queries for Primary and Secondary Zones during booting up (server started pinging but either showing applying settings etc.. or in a state where its waiting for all the services to be started)
Regards,
Ochen