added service info

Postgresql.md

@@ -27,6 +27,23 @@ sudo dnf install postgresql-server
 ```
 
 ## Setup
+First make sure postgres is running:
+```sh
+systemctl status postgresql.service
+```
+
+If not, start it with:
+```sh
+sudo systemctl start postgresql.service
+```
+
+If you want it to start on boot, you can enable it with:
+```sh
+sudo systemctl enable postgresql.service
+```
+
+To stop it from starting on boot, replace enable with disable.
+
 Initially the postgres database user will not have a password to allow access. To access the database run the following:
 ```sh
 sudo -u postgres psql