#!/bin/ksh
# $Id: mailmx,v 1.6 2008/10/26 18:53:16 ksb Exp $
# We're a netlint plugin that reports our lowest priority MX host   (petef,ksb)
# to the central netlint server (which will cross-reference with
# the netlint report from that mx host)

PROGNAME=`basename $0`
: ${CARP:=echo}
if [ _"$1" = _"-V" ]; then
	echo "$PROGNAME: "'$Id: mailmx,v 1.6 2008/10/26 18:53:16 ksb Exp $'
	exit 0
fi

HOST=`hostname`
if expr "$HOST" : "[^.]*" >/dev/null; then
	HOST="$HOST[^ 	]*"
fi

#****a* mail/MAIL_MX
# NAME
#   MAIL_MX
# FORMAT
#   MAIL_MX: name integer
# DESCRIPTION
#   This is the list of DNS MX records the host sees for itself from the local
#   resolver.
# REMEDIATION
#   Fix DNS errors in the zone file on master-source in /etc/namedb/master.
#***


# Get a list of IPs our hostname resolves to
nslookup -q=mx `hostname` 2>/dev/null |
	sed -n -e "s,^$HOST[ 	]*mail exchanger = \([0-9][0-9]*\) \(.*\)\.$,\1 \2,p" -e "s,^$HOST[ 	]*preference = \([0-9][0-9]*\)\, mail exchanger = \(.*\),\1 \2,p" |
	sort -n | head -1 |
	sed -n -e 's,^\([0-9]*\) \(.*\)$,MAIL_MX: \2 \1,p' |
	xapply -f "$CARP '%1'" -

exit 0