@@ -81,42 +81,43 @@ On the Docker host (192.168.1.52) that Redis will run on:

     ^D

     # add redis ambassador

-    $ docker run -t -i --link redis:redis --name redis_ambassador -p 6379:6379 busybox sh

+    $ docker run -t -i --link redis:redis --name redis_ambassador -p 6379:6379 alpine:3.2 sh

 In the `redis_ambassador` container, you can see the linked Redis

 containers `env`:

-    $ env

+    / # env

     REDIS_PORT=tcp://172.17.0.136:6379

     REDIS_PORT_6379_TCP_ADDR=172.17.0.136

     REDIS_NAME=/redis_ambassador/redis

     HOSTNAME=19d7adf4705e

+    SHLVL=1

+    HOME=/root

     REDIS_PORT_6379_TCP_PORT=6379

-    HOME=/

     REDIS_PORT_6379_TCP_PROTO=tcp

-    container=lxc

     REDIS_PORT_6379_TCP=tcp://172.17.0.136:6379

     TERM=xterm

     PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

     PWD=/

+    / # exit

 This environment is used by the ambassador `socat` script to expose Redis

 to the world (via the `-p 6379:6379` port mapping):

     $ docker rm redis_ambassador

-    $ sudo ./contrib/mkimage-unittest.sh

-    $ docker run -t -i --link redis:redis --name redis_ambassador -p 6379:6379 docker-ut sh

-

-    $ socat TCP4-LISTEN:6379,fork,reuseaddr TCP4:172.17.0.136:6379

+    $ CMD="apk update && apk add socat && sh"

+    $ docker run -t -i --link redis:redis --name redis_ambassador -p 6379:6379 alpine:3.2 sh -c "$CMD"

+    [...]

+    / # socat -t 100000000 TCP4-LISTEN:6379,fork,reuseaddr TCP4:172.17.0.136:6379

 Now ping the Redis server via the ambassador:

 Now go to a different server:

-    $ sudo ./contrib/mkimage-unittest.sh

-    $ docker run -t -i --expose 6379 --name redis_ambassador docker-ut sh

-

-    $ socat TCP4-LISTEN:6379,fork,reuseaddr TCP4:192.168.1.52:6379

+    $ CMD="apk update && apk add socat && sh"

+    $ docker run -t -i --expose 6379 --name redis_ambassador alpine:3.2 sh -c "$CMD"

+    [...]

+    / # socat -t 100000000 TCP4-LISTEN:6379,fork,reuseaddr TCP4:192.168.1.52:6379

 And get the `redis-cli` image so we can talk over the ambassador bridge.

@@ -127,8 +128,8 @@ And get the `redis-cli` image so we can talk over the ambassador bridge.

 ## The svendowideit/ambassador Dockerfile

-The `svendowideit/ambassador` image is a small `busybox` image with

-`socat` built in. When you start the container, it uses a small `sed`

+The `svendowideit/ambassador` image is based on the `alpine:3.2` image with

+`socat` installed. When you start the container, it uses a small `sed`

 script to parse out the (possibly multiple) link environment variables

 to set up the port forwarding. On the remote host, you need to set the

 variable using the `-e` command line option.

@@ -139,19 +140,21 @@ Will forward the local `1234` port to the remote IP and port, in this

 case `192.168.1.52:6379`.

     #

-    #

-    # first you need to build the docker-ut image

-    # using ./contrib/mkimage-unittest.sh

-    # then

-    #   docker build -t SvenDowideit/ambassador .

-    #   docker tag SvenDowideit/ambassador ambassador

+    # do

+    #   docker build -t svendowideit/ambassador .

     # then to run it (on the host that has the real backend on it)

-    #   docker run -t -i --link redis:redis --name redis_ambassador -p 6379:6379 ambassador

+    #   docker run -t -i -link redis:redis -name redis_ambassador -p 6379:6379 svendowideit/ambassador

     # on the remote host, you can set up another ambassador

-    #   docker run -t -i --name redis_ambassador --expose 6379 sh

+    #    docker run -t -i -name redis_ambassador -expose 6379 -e REDIS_PORT_6379_TCP=tcp://192.168.1.52:6379 svendowideit/ambassador sh

+    # you can read more about this process at https://docs.docker.com/articles/ambassador_pattern_linking/

-    FROM    docker-ut

-    MAINTAINER      SvenDowideit@home.org.au

+    # use alpine because its a minimal image with a package manager.

+    # prettymuch all that is needed is a container that has a functioning env and socat (or equivalent)

+    FROM	alpine:3.2

+    MAINTAINER	SvenDowideit@home.org.au

+    RUN apk update && \

+    	apk add socat && \

+    	rm -r /var/cache/

-    CMD     env | grep _TCP= | sed 's/.*_PORT_\([0-9]*\)_TCP=tcp:\/\/\(.*\):\(.*\)/socat TCP4-LISTEN:\1,fork,reuseaddr TCP4:\2:\3 \&/'  | sh && top

+    CMD	env | grep _TCP= | sed 's/.*_PORT_\([0-9]*\)_TCP=tcp:\/\/\(.*\):\(.*\)/socat -t 100000000 TCP4-LISTEN:\1,fork,reuseaddr TCP4:\2:\3 \& wait/' | sh

@@ -78,18 +78,20 @@ the `Using cache` message in the console output.

 (For more information, see the [Build cache section](../articles/dockerfile_best-practices.md#build-cache)) in the

 `Dockerfile` best practices guide:

-    $ docker build -t SvenDowideit/ambassador .

-    Uploading context 10.24 kB

-    Uploading context

-    Step 1 : FROM docker-ut

-     ---> cbba202fe96b

-    Step 2 : MAINTAINER SvenDowideit@home.org.au

+    $ docker build -t svendowideit/ambassador .

+    Sending build context to Docker daemon 15.36 kB

+    Step 0 : FROM alpine:3.2

+     ---> 31f630c65071

+    Step 1 : MAINTAINER SvenDowideit@home.org.au

      ---> Using cache

-     ---> 51182097be13

-    Step 3 : CMD env | grep _TCP= | sed 's/.*_PORT_\([0-9]*\)_TCP=tcp:\/\/\(.*\):\(.*\)/socat TCP4-LISTEN:\1,fork,reuseaddr TCP4:\2:\3 \&/'  | sh && top

+     ---> 2a1c91448f5f

+    Step 2 : RUN apk update &&      apk add socat &&        rm -r /var/cache/

      ---> Using cache

-     ---> 1a5ffc17324d

-    Successfully built 1a5ffc17324d

+     ---> 21ed6e7fbb73

+    Step 3 : CMD env | grep _TCP= | sed 's/.*_PORT_\([0-9]*\)_TCP=tcp:\/\/\(.*\):\(.*\)/socat -t 100000000 TCP4-LISTEN:\1,fork,reuseaddr TCP4:\2:\3 \& wait/' | sh

+     ---> Using cache

+     ---> 7ea8aef582cc

+    Successfully built 7ea8aef582cc

 When you're done with your build, you're ready to look into [*Pushing a

 repository to its registry*](../userguide/dockerrepos.md#contributing-to-docker-hub).