diff --git a/stack.sh b/stack.sh
index af01faa..22d184e 100755
--- a/stack.sh
+++ b/stack.sh
@@ -1083,7 +1083,7 @@
     die_if_not_set $LINENO NOVA_USER_ID "Failure retrieving NOVA_USER_ID for nova"
     NOVA_TENANT_ID=$(keystone tenant-list | grep " $SERVICE_TENANT_NAME " | get_field 1)
     die_if_not_set $LINENO NOVA_TENANT_ID "Failure retrieving NOVA_TENANT_ID for $SERVICE_TENANT_NAME"
-    CREDS=$(keystone ec2-credentials-create --user_id $NOVA_USER_ID --tenant_id $NOVA_TENANT_ID)
+    CREDS=$(keystone ec2-credentials-create --user-id $NOVA_USER_ID --tenant-id $NOVA_TENANT_ID)
     ACCESS_KEY=$(echo "$CREDS" | awk '/ access / { print $4 }')
     SECRET_KEY=$(echo "$CREDS" | awk '/ secret / { print $4 }')
     iniset $NOVA_CONF DEFAULT s3_access_key "$ACCESS_KEY"