OpenShift Advanced Cluster Management Observability
- Introduction
 - Pre-requisites
 - 1 - Logging into aws locally
 - 2 - Creating s3 bucket
 - 3 - Install openshift clusters
 - 4 - Install advanced cluster management
 - 5 - Enable acm observability
 - 6 - Import the single node openshift cluster into acm
 - 7 - Creating the edge workload
 
Introduction
This document captures the environment setup steps for a ~30 minute live demo of the Red Hat Advanced Cluster Management observability feature for OpenShift.
Pre-requisites
This guide assumes you:
- Have access to an Amazon Web Services account with permissions to be able to create resources including 
s3buckets andec2instances. In my case I have an AWS Blank Open Environment provisioned through the Red Hat demo system. - Already have the 
awsandoccli utilities installed. - Have registered for a Red Hat account (required for obtaining an OpenShift install image pull secret).
 
1 - Logging into aws locally
Our first step is to login to our aws account locally via the aws cli which will prompt for four values:
aws configure
2 - Creating s3 bucket
After logging into aws lets confirm our permissions are working by creating the s3 bucket we will need later on.
aws s3 mb "s3://open-cluster-management-observability" --region "$(aws configure get region)"
3 - Install openshift clusters
With our aws credentials working let's move on to deploying the hub and single node openshift cluster required for the live demo.
3.1 Download installer tools
Our first step will be to ensure we have an up to date version of the openshift-install cli tool. We can download it as follows:
# Download the installer
wget "https://mirror.openshift.com/pub/openshift-v4/$(uname -m)/clients/ocp/stable/openshift-install-linux.tar.gz"
# Extract the archive
tar xf openshift-install-linux.tar.gz openshift-install && rm openshift-install-linux.tar.gz*
3.2 Obtain install pull secret
Next we have a manual step to login to the Red Hat Hybrid Cloud Console and obtain our Pull Secret which will be required for our installation configuration.
Open the Console and click Download pull secret. This will download a file called pull-secret.txt which will be used later on.
Once the file downloads ensure it is copied or moved to the directory you will be running the remaining commands on this guide from.
3.3 Initiate the hub cluster install
Once our install tooling is available let's kick off the installation of our hub cluster by creating a configuration file and then running openshift-install.
cat << EOF > hub/install-config.yaml
additionalTrustBundlePolicy: Proxyonly
apiVersion: v1
baseDomain: $(aws route53 list-hosted-zones | jq '.HostedZones[0].Name' -r | sed 's/.$//')
compute:
- architecture: amd64
  hyperthreading: Enabled
  name: worker
  platform: {}
  replicas: 0
controlPlane:
  architecture: amd64
  hyperthreading: Enabled
  name: master
  platform: {}
  replicas: 3
metadata:
  creationTimestamp: null
  name: hub
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes
  serviceNetwork:
  - 172.30.0.0/16
platform:
  aws:
    region: $(aws configure get region)
publish: External
pullSecret: |
  $(cat pull-secret.txt)
EOF
Once the configuration file is created we can kick off the install with openshift-install as follows. The install process will generally take about half an hour.
./openshift-install create cluster --dir hub --log-level info
3.4 Initiate the sno cluster install
We can run our single node openshift cluster install at the same time in a separate terminal to speed things up.  The process is the same we will first create an install-config.yaml file, then run openshift-install.
cat << EOF > sno/install-config.yaml
additionalTrustBundlePolicy: Proxyonly
apiVersion: v1
baseDomain: $(aws route53 list-hosted-zones | jq '.HostedZones[0].Name' -r | sed 's/.$//')
compute:
- architecture: amd64
  hyperthreading: Enabled
  name: worker
  platform: {}
  replicas: 0
controlPlane:
  architecture: amd64
  hyperthreading: Enabled
  name: master
  platform: {}
  replicas: 1
metadata:
  creationTimestamp: null
  name: sno
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes
  serviceNetwork:
  - 172.30.0.0/16
platform:
  aws:
    region: $(aws configure get region)
publish: External
pullSecret: |
  $(cat pull-secret.txt)
EOF
Once the configuration file is created we can kick off the install with openshift-install as follows. The install process will generally take about half an hour.
./openshift-install create cluster --dir sno --log-level info
4 - Install advanced cluster management
To make use of the Red Hat Advanced Cluster Management Observability feature we need to first install Advanced Cluster Management on our hub cluster via the acm operator.
Let's get started by creating an OperatorGroup and Subscription which will install the operator.
oc --kubeconfig hub/auth/kubeconfig create namespace open-cluster-management
cat << EOF | oc --kubeconfig hub/auth/kubeconfig apply --filename -
apiVersion: operators.coreos.com/v1
kind: OperatorGroup
metadata:
  name: acm-operator-group
  namespace: open-cluster-management
spec:
  targetNamespaces:
    - open-cluster-management
---
apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
  name: acm-operator-subscription
  namespace: open-cluster-management
spec:
  sourceNamespace: openshift-marketplace
  source: redhat-operators
  channel: release-2.9
  installPlanApproval: Automatic
  name: advanced-cluster-management
EOF
Once the operator is installed we can create the MultiClusterHub resource to install Advanced Cluster Management.
Note: It can take up to ten minutes for this to complete.
cat << EOF | oc --kubeconfig hub/auth/kubeconfig apply --filename -
apiVersion: operator.open-cluster-management.io/v1
kind: MultiClusterHub
metadata:
  name: multiclusterhub
  namespace: open-cluster-management
  spec: {}
EOF
5 - Enable acm observability
Now, with our clusters deployed and acm installed we can enable the observability service by creating a MultiClusterObservability custom resource instance on the hub cluster.
Our first step towards this is to create two secrets.
oc --kubeconfig hub/auth/kubeconfig create namespace open-cluster-management-observability
DOCKER_CONFIG_JSON=`oc --kubeconfig hub/auth/kubeconfig extract secret/pull-secret -n openshift-config --to=-`
oc --kubeconfig hub/auth/kubeconfig create secret generic multiclusterhub-operator-pull-secret \
    -n open-cluster-management-observability \
    --from-literal=.dockerconfigjson="$DOCKER_CONFIG_JSON" \
    --type=kubernetes.io/dockerconfigjson
cat << EOF | oc --kubeconfig hub/auth/kubeconfig apply --filename -
apiVersion: v1
kind: Secret
metadata:
  name: thanos-object-storage
  namespace: open-cluster-management-observability
type: Opaque
stringData:
  thanos.yaml: |
    type: s3
    config:
      bucket: open-cluster-management-observability
      endpoint: s3.$(aws configure get region).amazonaws.com
      insecure: true
      access_key: $(aws configure get aws_access_key_id)
      secret_key: $(aws configure get aws_secret_access_key)
EOF
Once the two required secrets exist we can create the MultiClusterObservability resource as follows:
cat << EOF | oc --kubeconfig hub/auth/kubeconfig apply --filename -
apiVersion: observability.open-cluster-management.io/v1beta2
kind: MultiClusterObservability
metadata:
  name: observability
spec:
  observabilityAddonSpec: {}
  storageConfig:
    metricObjectStorage:
      name: thanos-object-storage
      key: thanos.yaml
EOF
After creating the resource and waiting briefyl we can access the grafana console via the Route to confirm everything is running:
echo "https://$(oc --kubeconfig hub/auth/kubeconfig get route -n open-cluster-management-observability grafana -o jsonpath={.spec.host})"
6 - Import the single node openshift cluster into acm
oc --kubeconfig hub/auth/kubeconfig new-project sno
oc --kubeconfig hub/auth/kubeconfig label namespace sno cluster.open-cluster-management.io/managedCluster=sno
cat << EOF | oc --kubeconfig hub/auth/kubeconfig apply --filename -
apiVersion: cluster.open-cluster-management.io/v1
kind: ManagedCluster
metadata:
  name: sno
spec:
  hubAcceptsClient: true
---
apiVersion: agent.open-cluster-management.io/v1
kind: KlusterletAddonConfig
metadata:
  name: sno
  namespace: sno
spec:
  clusterName: sno
  clusterNamespace: sno
  applicationManager:
    enabled: true
  certPolicyController:
    enabled: true
  clusterLabels:
    cloud: auto-detect
    vendor: auto-detect
  iamPolicyController:
    enabled: true
  policyController:
    enabled: true
  searchCollector:
    enabled: true
  version: 2.0.0
EOF
The ManagedCluster-Import-Controller will generate a secret named sno-import. The sno-import secret contains the import.yaml that the user applies to a managed cluster to install klusterlet.
oc --kubeconfig hub/auth/kubeconfig get secret sno-import -n sno -o jsonpath={.data.crds\\.yaml} | base64 --decode > klusterlet-crd.yaml
oc --kubeconfig hub/auth/kubeconfig get secret sno-import -n sno -o jsonpath={.data.import\\.yaml} | base64 --decode > import.yaml
oc --kubeconfig sno/auth/kubeconfig apply --filename klusterlet-crd.yaml
oc --kubeconfig sno/auth/kubeconfig apply --filename import.yaml
If everything works fine you should see JOINED and AVAILABLE sno cluster from within your hub cluster.
❯ kubectl get managedcluster -n sno
NAME            HUB ACCEPTED   MANAGED CLUSTER URLS                                           JOINED   AVAILABLE   AGE
local-cluster   true           https://api.hub.<yourdomain>.com:6443                          True     True        5h12m
sno             true           https://api.cluster-vzmvz.<yourdomain>.com:6443                True     True        31m
7 - Creating the edge workload
For edge scenarios we only send metrics to the hub cluster if certain thresholds are hit for a certain period of time (here 70% cpu for more than 2 minutes) - you can see this configuration in the open-cluster-management-addon-observability namespace under ConfigMaps observability-metrics-allowlist in the collect_rules section under SNOHighCPUUsage).
In order to hit that trigger we now deploy a cpu-heavy workload in order for sno-cluster metrics being sent to the ACM hub cluster.
Let's get started by creating a new project on the sno cluster:
oc new-project cpu-load-test
and deploy the cpu-load-container workload on a busybox container
cat << EOF | oc apply --filename -
apiVersion: apps/v1
kind: Deployment
metadata:
  name: cpu-load-test
spec:
  replicas: 5
  selector:
    matchLabels:
      app: cpu-load-test
  template:
    metadata:
      labels:
        app: cpu-load-test
    spec:
      containers:
      - name: cpu-load-container
        image: busybox
        command: ["/bin/sh", "-c"]
        args:
          - while true; do
              echo "Performing CPU load...";
              dd if=/dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 1000 | head -n 1000000 > /dev/null;
            done
EOF