diff --git a/xCAT-UI/lib/functions.php b/xCAT-UI/lib/functions.php
index 3fa8eded5..14ebc052c 100644
--- a/xCAT-UI/lib/functions.php
+++ b/xCAT-UI/lib/functions.php
@@ -5,6 +5,7 @@
 
 // Retain session variables across page requests
 session_start();
+session_write_close();	// Do not block HTTP requests
 
 // The settings below display error on the screen,
 // instead of giving blank pages.
@@ -307,7 +308,6 @@ function logout() {
 
 	// Clear server store of data
 	$_SESSION=array();
-	session_destroy();
 }
 
 /**
diff --git a/xCAT-UI/lib/log.php b/xCAT-UI/lib/log.php
index bd235d141..6e20b34d8 100644
--- a/xCAT-UI/lib/log.php
+++ b/xCAT-UI/lib/log.php
@@ -3,6 +3,8 @@ $TOPDIR = '..';
 require_once "$TOPDIR/lib/functions.php";
 require_once "$TOPDIR/lib/jsonwrapper.php";
 
+session_start();
+
 header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
 header("Cache-Control: no-store, no-cache, must-revalidate");
 header("Cache-Control: post-check=0, pre-check=0", false);
diff --git a/xCAT-UI/lib/srv_functions.php b/xCAT-UI/lib/srv_functions.php
index 3f427cab3..624db7687 100644
--- a/xCAT-UI/lib/srv_functions.php
+++ b/xCAT-UI/lib/srv_functions.php
@@ -5,6 +5,7 @@
 
 // Retain session variables across page requests
 session_start();
+session_write_close();	// Do not block HTTP requests
 
 // The settings below display error on the screen,
 // instead of giving blank pages.
@@ -319,6 +320,5 @@ function logout() {
 
 	// Clear server store of data
 	$_SESSION=array();
-	session_destroy();
 }
 ?>
diff --git a/xCAT-UI/lib/srv_log.php b/xCAT-UI/lib/srv_log.php
index 33a376cdc..5a9f3bccc 100644
--- a/xCAT-UI/lib/srv_log.php
+++ b/xCAT-UI/lib/srv_log.php
@@ -3,6 +3,8 @@ $TOPDIR = '..';
 require_once "$TOPDIR/lib/srv_functions.php";
 require_once "$TOPDIR/lib/jsonwrapper.php";
 
+session_start();
+
 header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
 header("Cache-Control: no-store, no-cache, must-revalidate");
 header("Cache-Control: post-check=0, pre-check=0", false);