Pushing an external and not yet published Docker image into Red Hat OpenShift V3

If you should have followed my previous postings ( thanks for that!! ), then you should have read my blog IMPORTING AN EXTERNAL AND NOT YET PUBLISHED DOCKER IMAGE INTO RED HAT OPENSHIFT V3, in which I have explained how to manually carry a Docker image from a non OpenShift build-server to our OpenShift infrastructure.

This time we want to reduce the effort and push our image directly from our build-server to OpenShift.

As it is recommended to only expose a secured OpenShift registry for remote access, we have to secure our registry.

Now let’s walk through the steps to push an existing image to our OpenShift V3 infrastructure.

Step 1 – To be performed on the OpenShift Master

Login to OpenShift via a console

# oc login
 Username: psteiner

When doing a push into a registry, OpenShifts expects the responding project to be already existing. So we need to create it first, or change into it, if it already exists

[psteiner@master certs.d]$ oc new-project iotdemo
Now using project "iotdemo" on server "https://master.example.com:8443".

Step 2 – To be performed on the OpenShift Master

Get your user-token and remember it for later steps

# oc whoami -t
 OI6I1JnQDOD-Dnmxtiysi0pnes2Eo4thMQxhxuwxgws

Step 3 – To be performed on the build-server

Identify the image, which you want to push to OpenShift

$ docker images 
REPOSITORY                    TAG    IMAGE ID     CREATED       VIRTUAL SIZE 
iotdemofuse_iotcontrollercep  latest c2471ec2cabc 22 hours ago  3.203 GB

Tag it with the right URL for the OpenShift registry

$ docker tag iotdemofuse_iotcontrollerreceiver registry.cloudapps.example.com/iotdemo/iotcontrollerreceiver

Lets’s analyse this command

$ docker tag iotdemofuse_iotcontrollerreceiver(1) registry.cloudapps.example.com(2)/iotdemo(3)/iotcontrollerreceiver(4)

1. the local name of the image
2. the URL of our remote OpenShift registry
3. the name of the target project on the OpenShift server, as created in step 1
4. the name of the image on the OpenShift

Step 4 – To be performed on the build-server

Login to the remote OpenShift registry. Please use the token, which you retrieved in step 2

$ docker login -u psteiner -e [email protected] -p OI6I1JnQDOD-Dnmxtiysi0pnes2Eo4thMQxhxuwxgws registry.cloudapps.example.com 
WARNING: login credentials saved in /home/psteiner/.docker/config.json 
Login Succeeded

Again, let’s analyse this command

$ docker login -u psteiner (1) -e [email protected] (2) -p OI6I1JnQDOD-Dnmxtiysi0pnes2Eo4thMQxhxuwxgws (3) registry.cloudapps.example.com (4)

1. your userID on OpenShift
2. some eMail-Address
3. the token, as retrieved in step 2
4. the URL of the OpenShift registry

Step 5 – To be performed on the build-server

Push the tagged image to OpenShift and use tag-value from step 3

$ docker push registry.cloudapps.example.com/iotdemo/iotcontrollerreceiver
The push refers to a repository [registry.cloudapps.example.com/iotdemo/iotcontrollerreceiver] (len: 1) 
4a1a9f0d3283: Image already exists 
47d44cb6f252: Image already exists 
Digest: sha256:d0a456315e44ebab465b04eaa8021f16472b494a290c035e78c07caa4300abc4

Step 6 – To be performed on the OpenShift Master

To verify a successful push of the image onto the OpenShift registry, we only need to check for the automatically created image-stream.

$ oc get is
NAME DOCKER REPO TAGS UPDATED
iotcontrollerreceiver 172.30.80.73:5000/iotdemo/iotcontrollerreceiver latest 8 minutes ago

All done! You have successfully pushed your image from a non-OpenShift build-server to your OpenShift system.