[Pkg-net-snmp-devel] Bug#640456: snmpd: init script may try to restart daemon before it terminates

[Saj Goonatilleke]

Package: snmpd
Version: 5.4.3~dfsg-2

Problem:

    `invoke-rc.d snmpd restart' may sometimes fail if the snmpd daemon 
    does not terminate by the time the init script's 2-second sleep 
    expires:

        invoke-rc.d: initscript snmpd, action "restart" failed.

    The chance of failure is significant enough at sites where 
    restarting snmpd across several hundred servers every day can 
    reliably trip it over.

Expected behaviour:

    The init script should wait for the daemon to terminate before 
    trying to start it back up again.  Adding --retry to 
    start-stop-daemon solved the problem for me.

Patch:

---------------------------------- 8< ----------------------------------
--- a/debian/snmpd.init
+++ b/debian/snmpd.init
@@ -55,18 +55,16 @@
     ;;
   stop)
     echo -n "Stopping network management services:"
-    start-stop-daemon --quiet --stop --oknodo --exec /usr/sbin/snmpd
+    start-stop-daemon --quiet --stop --oknodo --retry 2 --exec /usr/sbin/snmpd
     echo -n " snmpd"
-    start-stop-daemon --quiet --stop --oknodo --exec /usr/sbin/snmptrapd
+    start-stop-daemon --quiet --stop --oknodo --retry 2 --exec /usr/sbin/snmptrapd
     echo -n " snmptrapd"
     echo "."
     ;;
   restart)
     echo -n "Restarting network management services:"
-    start-stop-daemon --quiet --stop --oknodo --exec /usr/sbin/snmpd
-    start-stop-daemon --quiet --stop --oknodo --exec /usr/sbin/snmptrapd
-    # Allow the daemons time to exit completely.
-    sleep 2
+    start-stop-daemon --quiet --stop --oknodo --retry 2 --exec /usr/sbin/snmpd
+    start-stop-daemon --quiet --stop --oknodo --retry 2 --exec /usr/sbin/snmptrapd
     if [ "$SNMPDRUN" = "yes" -a -f /etc/snmp/snmpd.conf ]; then
        start-stop-daemon --quiet --start --exec /usr/sbin/snmpd -- $SNMPDOPTS
        echo -n " snmpd"
---------------------------------- >8 ----------------------------------

Thanks!