An image contains the code used to create a deployment. Then, a deployment can be created from an image, which should then create a replica set (which is the number of pods that should be created), and then the pods should be created.
There are various ways to deploy an app.
Before importing an image, the oc get images command can be used to determine if the image has already been imported.
~]# oc get images NAME IAMGE REFERENCE sha256:0089883f8e4387618946cd24378a447b8cf7e5dfaa146b94acab27fc5e170a14 registry.example.com/jboss-webserver-3/webserver30-tomcat8-openshift@sha256:0089883f8e4387618946cd24378a447b8cf7e5dfaa146b94acab27fc5e170a14 sha256:0155e28b6b10d6fba7144df9ce33105acbab32766836baacc67c76b900a58772 registry.example.com/redhat-sso-7/sso70-openshift@sha256:0155e28b6b10d6fba7144df9ce33105acbab32766836baacc67c76b900a58772 sha256:03416282b034b93614ab2af74441ce481226bcf0b0b6c614cacd1b6f008f9792 registry.example.com/jboss-eap-6/eap64-openshift@sha256:03416282b034b93614ab2af74441ce481226bcf0b0b6c614cacd1b6f008f9792 sha256:03795eb1e54f94ffb822b8b3997b5f5bbeaa20bdf7006841864738d1eb58054b registry.example.com/rhpam-7/rhpam72-businesscentral-openshift@sha256:03795eb1e54f94ffb822b8b3997b5f5bbeaa20bdf7006841864738d1eb58054b
The oc new-build command can be used to import an image from an external registry, such as GitHub. In this example, an image named camel-app is imported.
~]$ oc new-build fabric8/s2i-java~https://github.com/monodot/simple-camel-spring-boot-app --name=camel-app --> Found container image ec41b73 (20 months old) from Docker Hub for "fabric8/s2i-java" Java Applications ----------------- Platform for building and running plain Java applications (fat-jar and flat classpath) Tags: builder, java * An image stream tag will be created as "s2i-java:latest" that will track the source image * A source build using source code from https://github.com/monodot/simple-camel-spring-boot-app will be created * The resulting image will be pushed to image stream tag "my-demo-app:latest" * Every time "s2i-java:latest" changes a new build will be triggered --> Creating resources with label build=camel-app ... imagestream.image.openshift.io "s2i-java" created imagestream.image.openshift.io "camel-app" created buildconfig.build.openshift.io "camel-app" created --> Success
The oc get builds command can then be used to determine if the build is running.
~]$ oc get builds NAME TYPE FROM STATUS STARTED DURATION camel-app-1 Source Git Running 2 minutes ago
And the oc get imagestreams command should return something like this.
~]$ oc get is | grep -i demo camel-app image-registry.openshift-image-registry.svc:5000/foo/camel-app