Add documentation for WORDPRESS_DB_HOST

wordpress/README.md

@@ -29,15 +29,16 @@ Indonesia.
 The following environment variables are also honored for configuring your
 WordPress instance:
 
+ - `-e WORDPRESS_DB_HOST=...` (defaults to the IP and port of the linked `mysql` container)
  - `-e WORDPRESS_DB_USER=...` (defaults to "root")
- - `-e WORDPRESS_DB_PASSWORD=...` (defaults to the value of the `MYSQL_ROOT_PASSWORD` environment variable from the linked mysql container)
+ - `-e WORDPRESS_DB_PASSWORD=...` (defaults to the value of the `MYSQL_ROOT_PASSWORD` environment variable from the linked `mysql` container)
  - `-e WORDPRESS_DB_NAME=...` (defaults to "wordpress")
  - `-e WORDPRESS_AUTH_KEY=...`, `-e WORDPRESS_SECURE_AUTH_KEY=...`, `-e WORDPRESS_LOGGED_IN_KEY=...`, `-e WORDPRESS_NONCE_KEY=...`, `-e WORDPRESS_AUTH_SALT=...`, `-e WORDPRESS_SECURE_AUTH_SALT=...`, `-e WORDPRESS_LOGGED_IN_SALT=...`, `-e WORDPRESS_NONCE_SALT=...` (default to unique random SHA1s)
 
-If the `WORDPRESS_DB_NAME` specified does not already exist in the given MySQL
-container,  it will be created automatically upon container startup, provided
-that the `WORDPRESS_DB_USER` specified has the necessary permissions to create
-it.
+If the `WORDPRESS_DB_NAME` specified does not already exist on the given MySQL
+server, it will be created automatically upon startup of the `wordpress`
+container, provided that the `WORDPRESS_DB_USER` specified has the necessary
+permissions to create it.
 
 If you'd like to be able to access the instance from the host without the
 container's IP, standard port mappings can be used:
@@ -47,6 +48,11 @@ container's IP, standard port mappings can be used:
 Then, access it via `http://localhost:8080` or `http://host-ip:8080` in a
 browser.
 
+If you'd like to use an external database instead of a linked `mysql` container,
+specify the hostname and port with `WORDPRESS_DB_HOST`:
+
+    docker run --name some-wordpress -e WORDPRESS_DB_HOST=10.1.2.3:3306 -d wordpress
+
 # Supported Docker versions
 
 This image is officially supported on Docker version 1.4.1.

wordpress/content.md

@@ -19,15 +19,16 @@ Indonesia.
 The following environment variables are also honored for configuring your
 WordPress instance:
 
+ - `-e WORDPRESS_DB_HOST=...` (defaults to the IP and port of the linked `mysql` container)
  - `-e WORDPRESS_DB_USER=...` (defaults to "root")
- - `-e WORDPRESS_DB_PASSWORD=...` (defaults to the value of the `MYSQL_ROOT_PASSWORD` environment variable from the linked mysql container)
+ - `-e WORDPRESS_DB_PASSWORD=...` (defaults to the value of the `MYSQL_ROOT_PASSWORD` environment variable from the linked `mysql` container)
  - `-e WORDPRESS_DB_NAME=...` (defaults to "wordpress")
  - `-e WORDPRESS_AUTH_KEY=...`, `-e WORDPRESS_SECURE_AUTH_KEY=...`, `-e WORDPRESS_LOGGED_IN_KEY=...`, `-e WORDPRESS_NONCE_KEY=...`, `-e WORDPRESS_AUTH_SALT=...`, `-e WORDPRESS_SECURE_AUTH_SALT=...`, `-e WORDPRESS_LOGGED_IN_SALT=...`, `-e WORDPRESS_NONCE_SALT=...` (default to unique random SHA1s)
 
-If the `WORDPRESS_DB_NAME` specified does not already exist in the given MySQL
-container,  it will be created automatically upon container startup, provided
-that the `WORDPRESS_DB_USER` specified has the necessary permissions to create
-it.
+If the `WORDPRESS_DB_NAME` specified does not already exist on the given MySQL
+server, it will be created automatically upon startup of the `wordpress`
+container, provided that the `WORDPRESS_DB_USER` specified has the necessary
+permissions to create it.
 
 If you'd like to be able to access the instance from the host without the
 container's IP, standard port mappings can be used:
@@ -36,3 +37,8 @@ container's IP, standard port mappings can be used:
 
 Then, access it via `http://localhost:8080` or `http://host-ip:8080` in a
 browser.
+
+If you'd like to use an external database instead of a linked `mysql` container,
+specify the hostname and port with `WORDPRESS_DB_HOST`:
+
+    docker run --name some-wordpress -e WORDPRESS_DB_HOST=10.1.2.3:3306 -d wordpress