Listing 5 Failsafe updates to the Nagios Config Files are provided by this script, which gets the changes from CVS, checks for errors, and creates new mailing lists if necessary.

#!/bin/sh
# Get changes to the configs
# Check them for errors
# HUP Nagios
# Create mailing lists as required. 

HOME='/usr/local/nagios'
BIN="${HOME}/bin"
CFG='/etc/nagios'
STATUS="${HOME}/var/status"
LISTHOME='/usr/local/nagios/lists'
LISTMAKER="${BIN}/listmaker.sh" # <--the script from Listing 4


############ Get changes to the configs
echo "refreshing the conf files from CVS"
cd /etc/nagios/ && cvs update -dAC
chown nagios.nagios /etc/nagios/*


############# Check them for errors
echo "checking for configuration errors"

ERRORS=`${BIN}/nagios \
  -v ${CFG}/nagios.cfg | grep 'Total Errors' | awk '{print $3}'`
if [ -z $ERRORS ] || [ "$ERRORS" -gt 0 ]
then
    echo "ERRORS DETECTED"
    ${BIN}/nagios -v ${CFG}/nagios.cfg
    exit 1
fi

echo "no errors found =-] "


############### HUP Nagios
echo "stopping nagios"
/etc/init.d/nagios stop

echo "waiting for children to die..."
sleep 1

CHILDREN=`ps -A | grep nagios | wc  -l`
COUNTER=0
while [ ${CHILDREN} -gt 0 ]
do
    echo "still ${CHILDREN} children alive, waiting..."
    sleep 3
    CHILDREN=`ps -A | grep nagios | wc  -l`
    COUNTER=$(($COUNTER+1))
    if [ "$COUNTER" -gt 4 ]
    then
        echo "Killing impolitely, Weve been waiting too long"
        killall -9 nagios
    fi
done

echo "children dead, restarting parent"
/etc/init.d/nagios start

################### Create mailing lists as required. 
echo -n "Did you add any new hosts or commands? (y/n) > "
read

if echo ${REPLY} | egrep -q '^[yY]'
then
   find ${STATUS} -type f | sed -e \
     's/.*\/\([^\/]\+\)\/\([^\/]\+\)$/\1 \2/' | while read i
   do
      HOST=`echo $i | cut -d\   -f1 | tr '[:upper:]' '[:lower:]'`
      SERVICE=`echo $i | cut -d\   -f '2-' | tr '[:upper:]' \
               '[:lower:]' | tr ' ' '_'`
      if [ "${HOST}" != "${OLDHOST}" ] #must be a new host
      then
         if [  ! -e "${LISTHOME}/${HOST}-host" ]
         then
            echo "${HOST} host"  | $LISTMAKER
         fi
         OLDHOST=${HOST}
      fi
      if [ ! -e "${LISTHOME}/${HOST}-${SERVICE}" ]
      then
        echo ${HOST} ${SERVICE} | $LISTMAKER
      fi
      echo -n '.'
   done
fi
exit 0