#!/bin/sh
# Copyright (C) 2019 Checkmk GmbH - License: GNU General Public License v2
# This file is part of Checkmk (https://checkmk.com). It is subject to the terms and
# conditions defined in the file COPYING, which is part of this source code package.

# Reason for this no-op: shellcheck disable=... before the first command disables the error for the
# entire script.
:

# Disable unused variable error (needed to keep track of version)
# shellcheck disable=SC2034
CMK_VERSION="2.3.0p38"

# This check can be used to test the name resolution of a given host
# address using the local resolver of the system this script is
# running on.

HOSTADDRESSES=mathias-kettner.de

# shellcheck source=agents/cfg_examples/dnsclient.cfg
. "$MK_CONFDIR/dnsclient.cfg" 2>/dev/null

echo "<<<mrpe>>>"
for HOSTADDRESS in $HOSTADDRESSES; do
    ADDRESSES=$(nslookup "$HOSTADDRESS" | sed -n -e 1,3d -e '/^Address: *\(.*\)$/s//\1/p')
    if [ ! "$ADDRESSES" ]; then
        STATE=2
        OUTPUT="CRIT - $HOSTADDRESS could not be resolved"
    else
        STATE=0
        OUTPUT="OK - $HOSTADDRESS resolved into $ADDRESSES"
    fi
    echo "Resolve_$HOSTADDRESS $STATE $OUTPUT"
done