renaming

[shutils.git] / nsd / nsd-dynipwatch

diff --git a/nsd/nsd-dynipwatch b/nsd/nsd-dynipwatch
new file mode 100755 (executable)
index 0000000..bfdb840
--- /dev/null
+++ b/nsd/nsd-dynipwatch
@@ -0,0 +1,78 @@
+#!/bin/bash
+
+logfile=
+watchfile=
+
+while true; do
+       case $1 in
+               --log) logfile=$2; shift ;;
+               --watchfile) watchfile=$2; shift ;;
+               -h|--help)
+                       echo "$0 [--log logfile] [--watchfile /tmp/\${host}.ip] zonefile host"
+                       exit 0
+                       ;;
+               *) break ;;
+       esac
+       shift
+done
+
+
+zonefile=$1
+host=$2
+[ -z "${watchfile}" ] && watchfile=/tmp/${host}.ip
+[ -z "${logfile}" ] && logfile="/var/log/nsd-dynipwatch-${host}.log"
+
+
+echo "Watch ${watchfile} for host ${host} and update ${zonefile}. Logfile: ${logfile}"
+
+
+function getAddrFromZonefile # <host> <zonefile>
+{
+       egrep "^$1\\s.*\\sA\\s.*" $2 | egrep -o "([0-9]+\\.)+[0-9]+"
+}
+
+function setAddrInZonefile # <host> <zonefile> <addr>
+{
+       sed -i -e "s_^\\($1\\s.*A\\s.*\\s\\)\\([0-9]\\+\\.\\)\\+[0-9]\\+_\\1$3_g" "$2"
+}
+
+function getSerialFromZonefile # <zonefile>
+{
+       awk '/; serial/{print$1}' "$1"
+}
+
+function setSerialInZonefile # <zonefile> <serial>
+{
+       sed -i -e "s_^\\(.*\\s\\)[0-9]\+\\(\\s\\+; serial.*\\)_\\1$2\\2_g" "$1"
+}
+
+function run()
+{
+       while true; do
+               inotifywait -q -t 30 -e close_write "${watchfile}"  > /dev/null
+               ret=$?
+               [ "$ret" = "0" ] || continue
+
+               oldip=`getAddrFromZonefile "${host}" "${zonefile}"`
+               newip=`cat ${watchfile}`
+               echo "`date '+%a %F %T'` :: ${oldip} => ${newip}."
+
+               if ! echo "${newip}" | egrep -q "^([0-9]+\\.)+[0-9]+$"  ; then
+                       echo "Wrong format of new IP address."
+                       continue
+               fi
+
+               if ! [ "${oldip}" = "${newip}" ]; then
+                       serial=`getSerialFromZonefile "${zonefile}"`
+                       serial=$(( $serial + 1))
+                       echo " Update IP address. New serial ${serial}."
+                       setAddrInZonefile "${host}" "${zonefile}" "${newip}"
+                       setSerialInZonefile "${zonefile}" "${serial}"
+                       nsdc rebuild && nsdc reload && nsdc notify
+               fi
+       done
+}
+
+
+run >> $logfile
+