[Pdns-users] Remote Service Check

[ktm at rice.edu]

On Tue, Dec 02, 2014 at 07:25:55AM +0000, Phil Daws wrote:
> Good morning, all
> 
> Have you recently started to use PDNS and very impressed indeed.  Am wondering if any of you have an example LUA script for checking whether a remote service is available or not ie. is webserver A available if not return A record or webserver B
> 
> Many thanks, Phil
> 

Hi Phil,

Typically work done within a lua script is of very short duration. Otherwise
it causes your DNS resolution performance to be poor. Checking website status
can be a slow process, and while it is taking place other non-related site
DNS queries can block. I would set up monitoring outside of PDNS and then
update a file or map and have your LUA script check that instead of trying
to check to website status itself. This will keep all the slow parts out-
of-band from the DNS resolution/lookup path.

Regards,
Ken