diff --git a/xCAT-server-2.0/sbin/xcatd b/xCAT-server-2.0/sbin/xcatd
index 78687c395..66cb02fd6 100755
--- a/xCAT-server-2.0/sbin/xcatd
+++ b/xCAT-server-2.0/sbin/xcatd
@@ -551,6 +551,7 @@ sub plugin_command {
         if ($dispatch_requests) { 
 	        dispatch_request($req,$callback,$modname);
         } else {
+           undef $SIG{CHLD};
            ${"xCAT_plugin::".$modname."::"}{process_request}->($req,$callback,\&do_request);
         }
         $$progname=$oldprogname;
@@ -634,6 +635,7 @@ sub dispatch_request {
    #Since plugins may commonly experience this, a preprocess_request implementation
    #will for now be required for a command to be scaled through service nodes
    #If the plugin offers a preprocess method, use it to set the request array
+   undef $SIG{CHLD};
    if (defined(${"xCAT_plugin::".$modname."::"}{preprocess_request})) {
     $reqs = ${"xCAT_plugin::".$modname."::"}{preprocess_request}->($req,$dispatch_cb,\&do_request);
    } else { #otherwise, pass it in without hierarchy support
@@ -671,6 +673,7 @@ sub dispatch_request {
 	   syslog("local4|err","Error dispatching request: ".$@);
 	}
      } else {
+        undef $SIG{CHLD};
         ${"xCAT_plugin::".$modname."::"}{process_request}->($_,\&dispatch_callback,\&do_request);
      }
      exit;