diff --git a/xCAT-test/autotest/testcase/installation/reg_linux_SN_installation_hierarchy b/xCAT-test/autotest/testcase/installation/reg_linux_SN_installation_hierarchy
index fca8c5742..69e0d1b0b 100644
--- a/xCAT-test/autotest/testcase/installation/reg_linux_SN_installation_hierarchy
+++ b/xCAT-test/autotest/testcase/installation/reg_linux_SN_installation_hierarchy
@@ -3,6 +3,7 @@ os:Linux
 
 cmd:chtab key=nameservers site.value="<xcatmaster>"
 check:rc==0
+cmd:if [[ "__GETNODEATTR($$CN,arch)__" =~ "x86_64" ]];then chdef -t node -o $$CN vmstorage=dir:///var/lib/libvirt/images/ &&  mkvm $$CN -s 25G; fi
 
 cmd:makedns -n
 check:rc==0
diff --git a/xCAT-test/autotest/testcase/installation/ubuntu_diskless_installation_vm b/xCAT-test/autotest/testcase/installation/ubuntu_diskless_installation_vm
index 4e87d180a..98f25d6d8 100644
--- a/xCAT-test/autotest/testcase/installation/ubuntu_diskless_installation_vm
+++ b/xCAT-test/autotest/testcase/installation/ubuntu_diskless_installation_vm
@@ -2,6 +2,7 @@ start:Ubuntu_diskless_installation_flat_x86_vm
 os:Linux
 cmd:copycds $$ISO
 check:rc==0
+cmd:if [[ "__GETNODEATTR($$CN,arch)__" =~ "x86_64" ]];then chdef -t node -o $$CN vmstorage=dir:///var/lib/libvirt/images/ &&  mkvm $$CN -s 15G; fi
 cmd:makedns -n
 check:rc==0
 cmd:makedhcp -n