Deploying Applications to Multiple Clusters

Sending an Application to the Dev Clusters

In this use case we are going to deploy a sample application prometheus-example-app to our development clusters, that means that we're going to target clusters labeled as env: dev.

NOTE: Below commands should be run in HUB Cluster (where ACM is running)

1. Create the different ACM components we will be using in this example: Channel, PlacementRule, Application and Subscription:

   oc create -f https://raw.githubusercontent.com/lcolagio/lab-rhacm/master/usecase1/rhacm/channel.yaml
   oc create -f https://raw.githubusercontent.com/lcolagio/lab-rhacm/master/usecase1/rhacm/application.yaml
   oc create -f https://raw.githubusercontent.com/lcolagio/lab-rhacm/master/usecase1/rhacm/subscription.yaml
   oc create -f https://raw.githubusercontent.com/lcolagio/lab-rhacm/master/usecase1/rhacm/placementrule.yaml

2. Check ACM components:

   created project

   oc get project | grep usecase1

   created ACM Components

   oc get applications -A | grep usecase1
   oc get channel -A | grep usecase1
   oc get subscription -A | grep usecase1
   oc get placementrule -A | grep usecase1
   
   oc describe subscription usecase1-subscription1 -n usecase1-app

   oc get deployable -A | grep usecase1

   output:

   ocp3                      usecase1-subscription1-deployable-mbb6s                                         Subscription    apps.open-cluster-management.io/v1   83s    Deployed
   ocp4                      usecase1-subscription1-deployable-7xbqw                                         Subscription    apps.open-cluster-management.io/v1   83s    Deployed
   usecase1-app              usecase1-subscription1-deployable                                               Subscription    apps.open-cluster-management.io/v1   83s    Propagated
   usecase1-app              usecase1-subscription1-usecase1-application-prometheus-example-app-deployment   Deployment      apps/v1                              83s
   usecase1-app              usecase1-subscription1-usecase1-application-usecase1-ns-namespace               Namespace       v1                                   83s
   

3. How to edit an component ACM

   # Edit subscription
   oc edit subscription usecase1-subscription1 -n usecase1-app

   # Edit Placementrule to change cluster label selector from dev to qua by example
   oc edit placementrule usecase1-placementrule -n usecase1-app

4. How to Delete all created components for the sample application

   # on cluster Hub
   oc delete subscription usecase1-subscription1 -n usecase1-app
   oc delete placementrule usecase1-placementrule -n usecase1-app
   oc delete applications usecase1-app -n usecase1-app
   oc delete channel usecase1-channel -n usecase1-channel
   
   oc delete project usecase1-channel
   oc delete project usecase1-app
   
   # on managed cluster
   oc delete project usecase1-app