Here are a couple of tips you could use to help improve DNS performance. I am in the middle of quite a big Data Centre at the moment. As we are moving many servers to new infrastructure, we need to ensure we have no impact to the estate.
Below are some example that help you get the best performance, initially we had a couple of servers that were waiting for a login to certain machines as they could not reach the old DNS servers.
When you have the multiple name servers, you separate them on many lines, so like you see below.
nameserver 192.168.1.1
nameserver 10.0.0.1To improve DNS lookups, you can use these settings
options rotate
options timeout:1This will use both the name servers in rotation and wait 1 second for an answer before trying the next one.