The check_dns Plugin

check_dns v2.3git (monitoring-plugins 2.3git)
Copyright (c) 1999 Ethan Galstad <>
Copyright (c) 2000-2008 Monitoring Plugins Development Team

This plugin uses the nslookup program to obtain the IP address for the given host/domain query.
An optional DNS server to use may be specified.
If no DNS server is specified, the default server(s) specified in /etc/resolv.conf will be used.

check_dns -H host [-s server] [-a expected-address] [-n] [-A] [-t timeout] [-w warn] [-c crit] [-L]

 -h, --help
    Print detailed help screen
 -V, --version
    Print version information
    Read options from an ini file. See
    for usage and examples.
 -H, --hostname=HOST
    The name or address you want to query
 -s, --server=HOST
    Optional DNS server you want to use for the lookup
 -a, --expected-address=IP-ADDRESS|CIDR|HOST
    Optional IP-ADDRESS/CIDR you expect the DNS server to return. HOST must end
    with a dot (.). This option can be repeated multiple times (Returns OK if any
    value matches).
 -n, --expect-nxdomain
    Expect the DNS server to return NXDOMAIN (i.e. the domain was not found)
    Cannot be used together with -a
 -A, --expect-authority
    Optionally expect the DNS server to be authoritative for the lookup
 -w, --warning=seconds
    Return warning if elapsed time exceeds value. Default off
 -c, --critical=seconds
    Return critical if elapsed time exceeds value. Default off
 -L, --all
    Return critical if the list of expected addresses does not match all addresses
    returned. Default off
 -t, --timeout=INTEGER
    Seconds before connection times out (default: 10)

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use of this software. To submit patches or suggest improvements, send email