diff --git a/xCAT-server/sbin/xcatd b/xCAT-server/sbin/xcatd
index 16c896718..fb05f544e 100755
--- a/xCAT-server/sbin/xcatd
+++ b/xCAT-server/sbin/xcatd
@@ -1003,11 +1003,16 @@ my %immediatechildren;
 
 sub generic_reaper {
     local ($!);
+    #print "generic_reaper in $$...";
     while (($CHILDPID = waitpid(-1, WNOHANG)) > 0) {
-        if (($CHILDPID == $pid_UDP) && ($udpctl)) {
-
-            # got here because UDP child is gone
-            close($udpctl); $udpctl = 0;
+        #print "reaper for $CHILDPID...\n";
+        if ($CHILDPID == $pid_UDP) {
+            if ($udpctl) {
+                # got here because UDP child is gone
+                close($udpctl);
+                $udpctl = 0;
+            }
+            $pid_UDP = 0;
         }
         yield;
     }
@@ -1017,16 +1022,20 @@ sub generic_reaper {
 sub ssl_reaper {
     local ($!);
     my $numdone = 0;
+    #print "ssl_reaper in $$...";
     while (($CHILDPID = waitpid(-1, WNOHANG)) > 0) {
+        #print "reaper for $CHILDPID...\n";
         if ($immediatechildren{$CHILDPID}) {
             delete $immediatechildren{$CHILDPID};
             $sslclients--;
             $numdone--;
         }
-        if (($CHILDPID == $pid_UDP) && ($udpctl)) {
-
-            # got here because UDP child is gone
-            close($udpctl); $udpctl = 0;
+        if ($CHILDPID == $pid_UDP) {
+            if ($udpctl) {
+                # got here because UDP child is gone
+                close($udpctl);
+                $udpctl = 0;
+            }
             $pid_UDP = 0;
         }
         if ($CHILDPID == $cmdlog_svrpid) {
@@ -1041,32 +1050,36 @@ sub ssl_reaper {
 
 sub dispatch_reaper {
     local ($!);
+    #print "dispatch_reaper in $$...";
     while (($CHILDPID = waitpid(-1, WNOHANG)) > 0) {
+        #print "reaper for $CHILDPID...\n";
         if ($dispatched_children{$CHILDPID}) {
             delete $dispatched_children{$CHILDPID};
             $dispatch_children--;
         }
-        if (($CHILDPID == $pid_UDP) && ($udpctl)) {
-
-            # got here because UDP child is gone
-            close($udpctl); $udpctl = 0;
-        }
+        #if (($CHILDPID == $pid_UDP) && ($udpctl)) {
+        #
+        #    # got here because UDP child is gone
+        #    close($udpctl); $udpctl = 0;
+        #}
     }
     $SIG{CHLD} = \&dispatch_reaper;
 }
 
 sub plugin_reaper {
     local ($!);
+    #print "plugin_reaper in $$...";
     while (($CHILDPID = waitpid(-1, WNOHANG)) > 0) {
+        #print "reaper for $CHILDPID...\n";
         if ($plugin_children{$CHILDPID}) {
             delete $plugin_children{$CHILDPID};
             $plugin_numchildren--;
         }
-        if (($CHILDPID == $pid_UDP) && ($udpctl)) {
-
-            # got here because UDP child is gone
-            close($udpctl); $udpctl = 0;
-        }
+        #if (($CHILDPID == $pid_UDP) && ($udpctl)) {
+        #
+        #    # got here because UDP child is gone
+        #    close($udpctl); $udpctl = 0;
+        #}
     }
     $SIG{CHLD} = \&plugin_reaper;
 }
@@ -1162,6 +1175,7 @@ if (!defined $pid_MON) {
 }
 unless ($pid_MON) {
     $$progname = "xcatd: install monitor";
+    $pid_UDP = 0;
     close($udpctl); $udpctl = 0;
     do_installm_service;
     xexit(0);
@@ -1510,7 +1524,7 @@ until ($quit) {
     }
 
     if ($child == 0) {
-        close($udpctl); $udpctl = 0;
+        close($udpctl); $udpctl = 0; $pid_UDP=0;
         $SIG{TERM} = $SIG{INT} = 'DEFAULT';
         $SIG{CHLD} = \&generic_reaper;    # THROTTLE
         $listener->close;
@@ -1614,16 +1628,27 @@ if (open($mainpidfile, "<", "/var/run/xcat/mainservice.pid")) {
     close($mainpidfile);
 }
 if ($listener) { $listener->close; }
-my $lastpid;
-while (keys %immediatechildren || $pid_UDP || $cmdlog_svrpid || $pid_MON) {
-    $lastpid = wait();
+
+$SIG{CHLD} = "DEFAULT"; # Disable the signal handler and let wait to cover the children quit
+
+my $remains = keys %immediatechildren;
+xCAT::MsgUtils->trace(0, 'I', "xcatd is going to stop, waiting for $remains plugins to quit...");
+while ($remains || $pid_UDP || $cmdlog_svrpid || $pid_MON) {
+    my $lastpid = wait();
+    last if ($lastpid < 0);
+
+    # Found an valid child process
     if ($immediatechildren{$lastpid}) {
         delete $immediatechildren{$lastpid};
-    } elsif ($lastpid == $pid_UDP) {
+        $remains = keys %immediatechildren;
+    }
+    elsif ($lastpid == $pid_UDP) {
         $pid_UDP = 0;
-    } elsif ($lastpid == $cmdlog_svrpid) {
+    }
+    elsif ($lastpid == $cmdlog_svrpid) {
         $cmdlog_svrpid = 0;
-    } elsif ($lastpid == $pid_MON) {
+    }
+    elsif ($lastpid == $pid_MON) {
         $pid_MON = 0;
     }
 }