diff --git a/xCAT-test/autotest/testcase/packimg/cases0 b/xCAT-test/autotest/testcase/packimg/cases0
index 5e0fc612e..aeca509ea 100644
--- a/xCAT-test/autotest/testcase/packimg/cases0
+++ b/xCAT-test/autotest/testcase/packimg/cases0
@@ -3,17 +3,17 @@ os:Linux
 description:
 cmd:copycds $$ISO
 cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg /rootimg.bak;fi 
-cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz /rootimg.gz.bak;fi
+cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz /rootimg.cpio.gz.bak;fi
 cmd:genimage __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-netboot-compute
 check:rc==0
 cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 check:rc==0
 cmd:packimage -o __GETNODEATTR($$CN,os)__ -p compute -a __GETNODEATTR($$CN,arch)__ -m cpio
 check:rc==0
-cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 check:rc==0
-cmd:rm -rf  /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
-cmd:mv -f /rootimg.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:rm -rf  /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
+cmd:mv -f /rootimg.cpio.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 cmd:mv -f /rootimg.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 end
@@ -21,17 +21,17 @@ end
 start:packimage_p_a_o
 os:Linux
 cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg /rootimg.bak;fi
-cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz /rootimg.gz.bak;fi
+cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz /rootimg.cpio.gz.bak;fi
 cmd:genimage __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-netboot-compute
 check:rc==0
 cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 check:rc==0
 cmd:packimage -p compute -a __GETNODEATTR($$CN,arch)__ -o __GETNODEATTR($$CN,os)__
 check:rc==0
-cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 check:rc==0
-cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
-cmd:mv -f /rootimg.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
+cmd:mv -f /rootimg.cpio.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 cmd:mv -f /rootimg.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 end
@@ -40,17 +40,17 @@ start:packimage_imagename
 os:Linux
 description:
 cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg /rootimg.bak;fi
-cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz /rootimg.gz.bak;fi
+cmd:ls /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz;if [ $? -eq 0 ];then mv -f /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz /rootimg.cpio.gz.bak;fi
 cmd:genimage __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-netboot-compute
 check:rc==0
 cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 check:rc==0
 cmd:packimage __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-netboot-compute
 check:rc==0
-cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:ls -l /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 check:rc==0
-cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
-cmd:mv -f /rootimg.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.gz
+cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
+cmd:mv -f /rootimg.cpio.gz.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg.cpio.gz
 cmd:rm -rf /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 cmd:mv -f /rootimg.bak /install/netboot/__GETNODEATTR($$CN,os)__/__GETNODEATTR($$CN,arch)__/compute/rootimg
 end