Health Check feature in BIND ?
Lawrence K. Chen, P.Eng.
lkchen at ksu.edu
Mon Jun 17 18:55:47 UTC 2013
----- Original Message -----
> Dear All,
>
> I was just thinking whether it is possible to have a some type of
> health checking of servers through BIND DNS Server and DNS Server
> should replied to clients based on that only.
>
>
>
> i.e., Suppose I have two entries of www record for domain xyz.in
> having ip address 10.1.1.10 and 10.2.2.10.
>
> Now I want that my DNS Server should check whether the server is up
> or not before replying to clients.
>
> If one is down, then DNS server should reply the IP address of the
> second one.
>
>
>
> Although this is not a DNS Job and we should use Load-Balancer for
> this.
>
> But I just wanna to check whether this feature is available in Bind
> or in any Open-Source Program which in turn can be combined with
> BIND to achieve the desired result.
>
Well, doesn't DNS kind of already do this...if the first DNS server isn' up, then the user's resolver will timeout and try the next resolver....
OTOH, for Load-Balancer.... we use a BigIP LTM, where I have a pool with two DNS servers and use the DNS_Monitor script F5 (which basically does a 'dig @<node> <lookup-name> | grep <expected-response> >/dev/null' )
Works pretty well, one of the nodes is usually the first one I do when there's a bind update.
Additionally I hit all my DNS servers from nagios with the check_dns plugin.
More information about the bind-users
mailing list