DNS Redundancy

[Phil Mayers]

On 21/10/10 12:50, Stephane Bortzmeyer wrote:
>
> Unlike the failure of an authoritative name server, the failure of a
> resolver is not really transparent for the Unix stub resolver, as you
> have discovered. You may consider solutions using a redundancy at
> layer 3 such as VRRP or CARP.

Yeah, we've observed this.

Our primary and secondary DNS IPs are actually virtual IPs; one is via a 
layer4 loadbalancer, the other via an eBGP injected route (for 
diversity) pointing at 4 real resolvers.

You can alleviate it with nscd on the clients, but that has its own 
problems.