Keep the previous prod instance running to facilitate rollback

.gitlab-ci.yml

@@ -138,7 +138,6 @@ production-deploy:
     - ssh -o StrictHostKeyChecking=no $SSH_USERNAME@$prod_floating_ip sudo systemctl stop mariadb
     - ssh -o StrictHostKeyChecking=no $SSH_USERNAME@$prod_floating_ip sudo umount /var/lib/mysql && df -h
     - openstack server remove volume $prod_instance_id $prod_volume
-    - openstack server stop $prod_instance_id
 
     - export instance_volume=$(openstack server show $instance_id -c volumes_attached -f value | awk -F"'" '{print $4}')
     - echo "Detaching instance_volume_id=${instance_volume} from new instance=${instance_id}"