diff --git a/xCAT-server/share/xcat/ca/openssl.cnf.tmpl b/xCAT-server/share/xcat/ca/openssl.cnf.tmpl
index ddaf59786..f7a0200ec 100644
--- a/xCAT-server/share/xcat/ca/openssl.cnf.tmpl
+++ b/xCAT-server/share/xcat/ca/openssl.cnf.tmpl
@@ -98,6 +98,7 @@ emailAddress		= optional
 
 ####################################################################
 [ req ]
+default_md          = sha256
 default_bits		= 2048
 default_keyfile 	= private/ca-key.pem
 distinguished_name	= req_distinguished_name