Update deploy-to-ubuntu.md (#1019)

* Update deploy-to-ubuntu.md

rewrite of #813

* Update deploy-to-ubuntu.md

docs/deploy-to-ubuntu.md

@@ -17,4 +17,4 @@ python -m virtualenv env && source env/bin/activate && python -m pip install -U
 ./algo
 ```
 
-**Warning**: If you run Algo on your existing server, the iptables rules will be overwritten. If you don't want to overwrite the rules, you must deploy via `ansible-playbook` and skip the `iptables` tag as described in [deploy-from-ansible.md](deploy-from-ansible.md).
+**Warning**: Algo is intended to be run on a standalone server. If you run Algo on your existing server, the iptables rules will be overwritten. If you don't want to overwrite the rules, you must deploy via `ansible-playbook` and skip the `iptables` tag as described in [deploy-from-ansible.md](deploy-from-ansible.md). Other changes are also made, which can break other services running on your server (web, mail, etc.).