From a7fd694f19a853021c08303debafae18cb1f3bff Mon Sep 17 00:00:00 2001
From: PJLindsay <PJLindsay@users.noreply.github.com>
Date: Fri, 13 Jul 2018 12:06:04 -0600
Subject: [PATCH] Update tut0.rst (#159)

* Update tut0.rst

Add hint about port mapping for users with pre-existing PostgreSQL DB
---
 tutorials/tut0.rst | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tutorials/tut0.rst b/tutorials/tut0.rst
index dc3d6b101..8ff68e6e5 100644
--- a/tutorials/tut0.rst
+++ b/tutorials/tut0.rst
@@ -35,6 +35,16 @@ If Docker is not installed, you can get it `here <https://www.docker.com/communi
 
 This will run the Docker instance as a daemon and expose port 5432 to the host system so that it looks like an ordinary PostgreSQL server to the rest of the system.
 
+.. note::
+
+  If you have a pre-existing PostgreSQL database running on port 5432, you'll get an error like "bind: address already in use". Here's how to fix it:
+
+  .. code-block:: bash
+
+    sudo docker run --name tutorial -p 5433:5432 \
+                    -e POSTGRES_PASSWORD=mysecretpassword \
+                    -d postgres
+
 Step 3. Install PostgREST
 -------------------------