diff --git a/xCAT-test/autotest/testcase/installation/reg_linux_diskfull_installation_flat b/xCAT-test/autotest/testcase/installation/reg_linux_diskfull_installation_flat
index 5c73b4917..c8f54d1b5 100644
--- a/xCAT-test/autotest/testcase/installation/reg_linux_diskfull_installation_flat
+++ b/xCAT-test/autotest/testcase/installation/reg_linux_diskfull_installation_flat
@@ -54,4 +54,8 @@ check:rc==0
 check:output=~\d\d:\d\d:\d\d
 cmd:xdsh $$CN mount
 check:rc==0
+cmd:sleep 120
+cmd:ping $$CN -c 3
+check:rc==0
+check:output=~64 bytes from $$CN
 end
diff --git a/xCAT-test/autotest/testcase/installation/reg_linux_diskless_installation_flat b/xCAT-test/autotest/testcase/installation/reg_linux_diskless_installation_flat
index 705400a6a..812eb0daf 100644
--- a/xCAT-test/autotest/testcase/installation/reg_linux_diskless_installation_flat
+++ b/xCAT-test/autotest/testcase/installation/reg_linux_diskless_installation_flat
@@ -63,6 +63,10 @@ check:output=~\d\d:\d\d:\d\d
 cmd:xdsh $$CN mount
 check:rc==0
 check:output=~on / type tmpfs
+cmd:sleep 120
+cmd:ping $$CN -c 3
+check:rc==0
+check:output=~64 bytes from $$CN
 
 cmd:rootimgdir=`lsdef -t osimage  __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-netboot-compute|grep rootimgdir|awk -F'=' '{print $2}'`; if [ -d $rootimgdir.regbak ]; then rm -rf $rootimgdir; mv $rootimgdir.regbak $rootimgdir; fi
 check:rc==0
diff --git a/xCAT-test/autotest/testcase/installation/reg_linux_statelite_installation_flat b/xCAT-test/autotest/testcase/installation/reg_linux_statelite_installation_flat
index c0ba9c8f8..a9759d66f 100644
--- a/xCAT-test/autotest/testcase/installation/reg_linux_statelite_installation_flat
+++ b/xCAT-test/autotest/testcase/installation/reg_linux_statelite_installation_flat
@@ -117,6 +117,10 @@ cmd:xdsh $$CN mount
 check:rc==0
 check:output=~/nodedata/$$CN on /.statelite/persistent
 check:output=~rootfs on / type tmpfs
+cmd:sleep 120
+cmd:ping $$CN -c 3
+check:rc==0
+check:output=~64 bytes from $$CN
 
 cmd:rootimgdir=`lsdef -t osimage  __GETNODEATTR($$CN,os)__-__GETNODEATTR($$CN,arch)__-statelite-compute|grep rootimgdir|awk -F'=' '{print $2}'`; if [ -d $rootimgdir.regbak ]; then rm -rf $rootimgdir; mv $rootimgdir.regbak $rootimgdir; fi
 check:rc==0