More check_dig needed options

[fpoulain]

Hi,

I would like to monitor if my NS records are still defined as I want and that there is no unwanted record. Unfortunately, check_dig doesn't allow this.

The '-a' option should be repeatable, allowing to define more than one address to expect in the answer (like for check_dns).

There is no way to indicate that I don't want any other answer than expected. Maybe the simple way to deal with that should be to add an option strictly checking the number of records in the answer.

How do you think about it?