in:
Univention Configuration Registry
we have 3 settings
dns/forwarder1
dns/forwarder2
dns/forwarder3
the UCS system uses these forwarders to resolve any DNS query it does not have an answer for.
Are they selected “round-robin”?
are do they switch the first time a resolver fails to return a valid address?
do they stay “switched” until the next bad query or do they reset back to the base one.