check_dnsext

Project Notes

NAME
check_dnsext - nagios plugin to check dns queries

DESCRIPTION
Nagios plugin to check the dns resolution of hostnames. As opposed to the official nagios plugin check_dns, this plugin allows to specify types of dns resource records, like SRV, MX, TXT.

VERSION
This documentation refers to <check_dnsext> version 0.0.2

USAGE
check_dnsext -H hostname -a expected_addres [-t type -s server -v]

REQUIRED ARGUMENTS
-H | --host

hostname (simple or fully qualified) or ip address that we want to check. This can also be a domain name (TLD) if checking a SOA, NS, MX resource record.

-a | --expected-address

Expected outcome of the dns query. If we expect a multi valued outcome, then use a comma to separate them. For example:

--expected-address=host.domain.tld,host2.domain.tld,host3.domain.tld,..

OPTIONS
-H | --host

hostname (simple or fully qualified) or ip address that we want to check. This can also be a domain name (TLD) if checking a SOA, NS, MX resource record.

-a | --expected-address

Expected outcome of the dns query. If we expect a multi valued outcome, then use a comma to separate them. For example:

--expected-address=host.domain.tld,host2.domain.tld,host3.domain.tld,..

-s | --server

dns server we want to use. If not specified, the default dns resolver of the system will be used.

-t | --type

type of dns resource record we want to query. If not specified, this defaults to an A record.

-v | --verbose

extra debugging info. Valid values are 0 (standard, no need to set it explicitely) or 1.

-h | -? | --help

this text

CONFIGURATION AND ENVIRONMENT
To use it in Nagios copy this file to your plugins folder (usually in /usr/local/nagios/libexec/ ). Make it executable for the nagios user.

DEPENDENCIES
This plugin requires the Net::DNS and the Array::Compare Perl modules. If you use a Redhat based linux distribution, you can install Net::DNS so:

# yum install perl-Net-DNS

The Array::Compare module is unfortunately not packaged in any of the usual yum repositories but building a spec file and creating a rpm package is for this one very straight forward. Dave Cross wrote a nice presentation showing how to achieve this: Perl in RPM-Land. You can read it in http://www.slideshare.net/davorg/perl-in-rpmland-presentation

If you use a debian based linux distribution, the modules are called libnet-dns-perl and libarray-compare-perl:

# apt-get install libnet-dns-perl
# apt-get install libarray-compare-perl

If you use another system, you should probably have to use the cpan shell to install them. You could use perlbrew or cpanminus as well.

AUTHOR
Natxo Asenjo ([email protected]_removethis_)

LICENCE AND COPYRIGHT
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perldoc perlartistic.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.