From 29a20672c216e2f8aa90af765ac5c47e3350b3d9 Mon Sep 17 00:00:00 2001 From: Ian Bull Date: Thu, 3 Jul 2014 22:40:02 -0700 Subject: [PATCH] Fix the parent/child relationship in the docs In the Docker Linking Docs, the parent child relationship was backwards. The Web container should be able to access the DB, not other way around. Furthermore, the output of 'docker ps' was wrong (it showed that the DB could access the Web). This fixes both typos. Docker-DCO-1.1-Signed-off-by: Ian Bull (github: irbull) --- docs/sources/userguide/dockerlinks.md | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/docs/sources/userguide/dockerlinks.md b/docs/sources/userguide/dockerlinks.md index 20a5c1a179..91c6cb355b 100644 --- a/docs/sources/userguide/dockerlinks.md +++ b/docs/sources/userguide/dockerlinks.md @@ -149,16 +149,16 @@ Let's look at our linked containers using `docker ps`. $ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES - 349169744e49 training/postgres:latest su postgres -c '/usr About a minute ago Up About a minute 5432/tcp db - aed84ee21bde training/webapp:latest python app.py 16 hours ago Up 2 minutes 0.0.0.0:49154->5000/tcp db/web,web + 349169744e49 training/postgres:latest su postgres -c '/usr About a minute ago Up About a minute 5432/tcp db, web/db + aed84ee21bde training/webapp:latest python app.py 16 hours ago Up 2 minutes 0.0.0.0:49154->5000/tcp web -We can see our named containers, `db` and `web`, and we can see that the `web` -containers also shows `db/web` in the `NAMES` column. This tells us that the +We can see our named containers, `db` and `web`, and we can see that the `db` +containers also shows `web/db` in the `NAMES` column. This tells us that the `web` container is linked to the `db` container in a parent/child relationship. So what does linking the containers do? Well we've discovered the link creates a parent-child relationship between the two containers. The parent container, -here `db`, can access information on the child container `web`. To do this +here `web`, can access information on the child container `db`. To do this Docker creates a secure tunnel between the containers without the need to expose any ports externally on the container. You'll note when we started the `db` container we did not use either of the `-P` or `-p` flags. As we're