I have a home network with 2 Macs (10.4 and 10.6) and one Linux box. There is a caching DNS nameserver on the Linux box. I would like the Macs to use the caching server, and only if that is inaccessible fall through to external DNS.
Do Macs rotate through all the configured nameservers or try them in order until one works?
I see that "man resolver" under 10.6 says that "if there are multiple servers, the resolver library queries them in the order listed", i.e., yes, it's round-robin as I want and as the RFC specifies.
However, I vaguely recall reading somewhere that not all Mac software uses this resolver library. But I could be misremembering. Can someone confirm that normal Mac DNS resolution is round-robin?
On 10.6 at least (and maybe 10.4) open System Preferences->Network pane, Advanced button, DNS tab and put the order of DNS servers you want to use.
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