Some options that may help in /etc/resolv.conf
Rotate through all listed servers-Mostly for load balancing
options rotate
options timeout:2
Default value is 5, range is 2 to 30
options attempts:2
Range starts at zero.
multiples are entered on one line:
options rotate timeout:2 attempts:1
For server to server connectivity that have static IP's, consider adding entries to the hosts file. And of course when a DNS server drops or is dropped out of service, change the DHCP DNS parameter to list the up server first.
edit: Then your help desk can quickly do a dhcp renewal for windows callers with ipconfig /renew
Of course these will only work on hosts with static IP's.
Edit: And there is a
sticky here from the security forum on a recent bind issue.