Chapter 8. High availability for hosted control planes

Procedure

1. Log in to an etcd pod by entering the following command:

   $ oc rsh -n <hosted_control_plane_namespace> -c etcd <etcd_pod_name>

2. Print the health status of an etcd cluster by entering the following command:

   sh-4.4$ etcdctl endpoint health --cluster -w table

   Example output

   ENDPOINT                                                HEALTH  TOOK        ERROR
   https://etcd-0.etcd-discovery.clusters-hosted.svc:2379  true    9.117698ms

Procedure

1. To confirm that the etcd pod is failing, enter the following command:

   $ oc get pods -l app=etcd -n <hosted_control_plane_namespace>

   Example output

   NAME     READY   STATUS             RESTARTS     AGE
   etcd-0   2/2     Running            0            64m
   etcd-1   2/2     Running            0            45m
   etcd-2   1/2     CrashLoopBackOff   1 (5s ago)   64m

   The failing etcd pod might have the CrashLoopBackOff or Error status.

2. Delete the failing pod and its PVC by entering the following command:

   $ oc delete pvc/<etcd_pvc_name> pod/<etcd_pod_name> --wait=false

Procedure

1. First, set up your environment variables and scale down the API servers:

   1. Set up environment variables for your hosted cluster by entering the following commands, replacing values as necessary:

      $ CLUSTER_NAME=my-cluster

      $ HOSTED_CLUSTER_NAMESPACE=clusters

      $ CONTROL_PLANE_NAMESPACE="${HOSTED_CLUSTER_NAMESPACE}-${CLUSTER_NAME}"

   2. Pause reconciliation of the hosted cluster by entering the following command, replacing values as necessary:

      $ oc patch -n ${HOSTED_CLUSTER_NAMESPACE} hostedclusters/${CLUSTER_NAME} -p '{"spec":{"pausedUntil":"true"}}' --type=merge

   3. Scale down the API servers by entering the following commands:

      1. Scale down the kube-apiserver:

         $ oc scale -n ${CONTROL_PLANE_NAMESPACE} deployment/kube-apiserver --replicas=0

      2. Scale down the openshift-apiserver:

         $ oc scale -n ${CONTROL_PLANE_NAMESPACE} deployment/openshift-apiserver --replicas=0

      3. Scale down the openshift-oauth-apiserver:

         $ oc scale -n ${CONTROL_PLANE_NAMESPACE} deployment/openshift-oauth-apiserver --replicas=0

2. Next, take a snapshot of etcd by using one of the following methods:

   1. Use a previously backed-up snapshot of etcd.

   2. If you have an available etcd pod, take a snapshot from the active etcd pod by completing the following steps:

      1. List etcd pods by entering the following command:

         $ oc get -n ${CONTROL_PLANE_NAMESPACE} pods -l app=etcd

      2. Take a snapshot of the pod database and save it locally to your machine by entering the following commands:

         $ ETCD_POD=etcd-0

         $ oc exec -n ${CONTROL_PLANE_NAMESPACE} -c etcd -t ${ETCD_POD} -- env ETCDCTL_API=3 /usr/bin/etcdctl \
         --cacert /etc/etcd/tls/etcd-ca/ca.crt \
         --cert /etc/etcd/tls/client/etcd-client.crt \
         --key /etc/etcd/tls/client/etcd-client.key \
         --endpoints=https://localhost:2379 \
         snapshot save /var/lib/snapshot.db

      3. Verify that the snapshot is successful by entering the following command:

         $ oc exec -n ${CONTROL_PLANE_NAMESPACE} -c etcd -t ${ETCD_POD} -- env ETCDCTL_API=3 /usr/bin/etcdctl -w table snapshot status /var/lib/snapshot.db

   3. Make a local copy of the snapshot by entering the following command:

      $ oc cp -c etcd ${CONTROL_PLANE_NAMESPACE}/${ETCD_POD}:/var/lib/snapshot.db /tmp/etcd.snapshot.db

      1. Make a copy of the snapshot database from etcd persistent storage:

         1. List etcd pods by entering the following command:

            $ oc get -n ${CONTROL_PLANE_NAMESPACE} pods -l app=etcd

         2. Find a pod that is running and set its name as the value of ETCD_POD: ETCD_POD=etcd-0, and then copy its snapshot database by entering the following command:

            $ oc cp -c etcd ${CONTROL_PLANE_NAMESPACE}/${ETCD_POD}:/var/lib/data/member/snap/db /tmp/etcd.snapshot.db

3. Next, scale down the etcd statefulset by entering the following command:

   $ oc scale -n ${CONTROL_PLANE_NAMESPACE} statefulset/etcd --replicas=0

   1. Delete volumes for second and third members by entering the following command:

      $ oc delete -n ${CONTROL_PLANE_NAMESPACE} pvc/data-etcd-1 pvc/data-etcd-2

   2. Create a pod to access the first etcd member’s data:

      1. Get the etcd image by entering the following command:

         $ ETCD_IMAGE=$(oc get -n ${CONTROL_PLANE_NAMESPACE} statefulset/etcd -o jsonpath='{ .spec.template.spec.containers[0].image }')

      2. Create a pod that allows access to etcd data:

         $ cat << EOF | oc apply -n ${CONTROL_PLANE_NAMESPACE} -f -
         apiVersion: apps/v1
         kind: Deployment
         metadata:
           name: etcd-data
         spec:
           replicas: 1
           selector:
             matchLabels:
               app: etcd-data
           template:
             metadata:
               labels:
                 app: etcd-data
             spec:
               containers:
               - name: access
                 image: $ETCD_IMAGE
                 volumeMounts:
                 - name: data
                   mountPath: /var/lib
                 command:
                 - /usr/bin/bash
                 args:
                 - -c
                 - |-
                   while true; do
                     sleep 1000
                   done
               volumes:
               - name: data
                 persistentVolumeClaim:
                   claimName: data-etcd-0
         EOF

      3. Check the status of the etcd-data pod and wait for it to be running by entering the following command:

         $ oc get -n ${CONTROL_PLANE_NAMESPACE} pods -l app=etcd-data

      4. Get the name of the etcd-data pod by entering the following command:

         $ DATA_POD=$(oc get -n ${CONTROL_PLANE_NAMESPACE} pods --no-headers -l app=etcd-data -o name | cut -d/ -f2)

   3. Copy an etcd snapshot into the pod by entering the following command:

      $ oc cp /tmp/etcd.snapshot.db ${CONTROL_PLANE_NAMESPACE}/${DATA_POD}:/var/lib/restored.snap.db

   4. Remove old data from the etcd-data pod by entering the following commands:

      $ oc exec -n ${CONTROL_PLANE_NAMESPACE} ${DATA_POD} -- rm -rf /var/lib/data

      $ oc exec -n ${CONTROL_PLANE_NAMESPACE} ${DATA_POD} -- mkdir -p /var/lib/data

   5. Restore the etcd snapshot by entering the following command:

      $ oc exec -n ${CONTROL_PLANE_NAMESPACE} ${DATA_POD} -- etcdutl snapshot restore /var/lib/restored.snap.db \
           --data-dir=/var/lib/data --skip-hash-check \
           --name etcd-0 \
           --initial-cluster-token=etcd-cluster \
           --initial-cluster etcd-0=https://etcd-0.etcd-discovery.${CONTROL_PLANE_NAMESPACE}.svc:2380,etcd-1=https://etcd-1.etcd-discovery.${CONTROL_PLANE_NAMESPACE}.svc:2380,etcd-2=https://etcd-2.etcd-discovery.${CONTROL_PLANE_NAMESPACE}.svc:2380 \
           --initial-advertise-peer-urls https://etcd-0.etcd-discovery.${CONTROL_PLANE_NAMESPACE}.svc:2380

   6. Remove the temporary etcd snapshot from the pod by entering the following command:

      $ oc exec -n ${CONTROL_PLANE_NAMESPACE} ${DATA_POD} -- rm /var/lib/restored.snap.db

   7. Delete data access deployment by entering the following command:

      $ oc delete -n ${CONTROL_PLANE_NAMESPACE} deployment/etcd-data

   8. Scale up the etcd cluster by entering the following command:

      $ oc scale -n ${CONTROL_PLANE_NAMESPACE} statefulset/etcd --replicas=3

   9. Wait for the etcd member pods to return and report as available by entering the following command:

      $ oc get -n ${CONTROL_PLANE_NAMESPACE} pods -l app=etcd -w

   10. Scale up all etcd-writer deployments by entering the following command:

       $ oc scale deployment -n ${CONTROL_PLANE_NAMESPACE} --replicas=3 kube-apiserver openshift-apiserver openshift-oauth-apiserver

4. Restore reconciliation of the hosted cluster by entering the following command:

   $ oc patch -n ${CLUSTER_NAMESPACE} hostedclusters/${CLUSTER_NAME} -p '{"spec":{"pausedUntil":""}}' --type=merge

Procedure

1. Pause reconciliation of the hosted cluster by entering the following command:

   $ oc patch -n clusters hostedclusters/<hosted_cluster_name> -p '{"spec":{"pausedUntil":"true"}}' --type=merge

2. Stop all etcd-writer deployments by entering the following command:

   $ oc scale deployment -n <hosted_cluster_namespace> --replicas=0 kube-apiserver openshift-apiserver openshift-oauth-apiserver

3. To take an etcd snapshot, use the exec command in each etcd container by entering the following command:

   $ oc exec -it <etcd_pod_name> -n <hosted_cluster_namespace> -- env ETCDCTL_API=3 /usr/bin/etcdctl --cacert /etc/etcd/tls/client/etcd-client-ca.crt --cert /etc/etcd/tls/client/etcd-client.crt --key /etc/etcd/tls/client/etcd-client.key --endpoints=localhost:2379 snapshot save /var/lib/data/snapshot.db

4. To check the snapshot status, use the exec command in each etcd container by running the following command:

   $ oc exec -it <etcd_pod_name> -n <hosted_cluster_namespace> -- env ETCDCTL_API=3 /usr/bin/etcdctl -w table snapshot status /var/lib/data/snapshot.db

5. Copy the snapshot data to a location where you can retrieve it later, such as an S3 bucket. See the following example.

   Note

   The following example uses signature version 2. If you are in a region that supports signature version 4, such as the us-east-2 region, use signature version 4. Otherwise, when copying the snapshot to an S3 bucket, the upload fails.

   Example

   BUCKET_NAME=somebucket
   FILEPATH="/${BUCKET_NAME}/${CLUSTER_NAME}-snapshot.db"
   CONTENT_TYPE="application/x-compressed-tar"
   DATE_VALUE=`date -R`
   SIGNATURE_STRING="PUT\n\n${CONTENT_TYPE}\n${DATE_VALUE}\n${FILEPATH}"
   ACCESS_KEY=accesskey
   SECRET_KEY=secret
   SIGNATURE_HASH=`echo -en ${SIGNATURE_STRING} | openssl sha1 -hmac ${SECRET_KEY} -binary | base64`
   
   oc exec -it etcd-0 -n ${HOSTED_CLUSTER_NAMESPACE} -- curl -X PUT -T "/var/lib/data/snapshot.db" \
     -H "Host: ${BUCKET_NAME}.s3.amazonaws.com" \
     -H "Date: ${DATE_VALUE}" \
     -H "Content-Type: ${CONTENT_TYPE}" \
     -H "Authorization: AWS ${ACCESS_KEY}:${SIGNATURE_HASH}" \
     https://${BUCKET_NAME}.s3.amazonaws.com/${CLUSTER_NAME}-snapshot.db

6. To restore the snapshot on a new cluster later, save the encryption secret that the hosted cluster references.

   1. Get the secret encryption key by entering the following command:

      $ oc get hostedcluster <hosted_cluster_name> -o=jsonpath='{.spec.secretEncryption.aescbc}'
      {"activeKey":{"name":"<hosted_cluster_name>-etcd-encryption-key"}}

   2. Save the secret encryption key by entering the following command:

      $ oc get secret <hosted_cluster_name>-etcd-encryption-key -o=jsonpath='{.data.key}'

      You can decrypt this key when restoring a snapshot on a new cluster.

Procedure

1. On the aws command-line interface (CLI), create a pre-signed URL so that you can download your etcd snapshot from S3 without passing credentials to the etcd deployment:

   ETCD_SNAPSHOT=${ETCD_SNAPSHOT:-"s3://${BUCKET_NAME}/${CLUSTER_NAME}-snapshot.db"}
   ETCD_SNAPSHOT_URL=$(aws s3 presign ${ETCD_SNAPSHOT})

2. Modify the HostedCluster specification to refer to the URL:

   spec:
     etcd:
       managed:
         storage:
           persistentVolume:
             size: 4Gi
           type: PersistentVolume
           restoreSnapshotURL:
           - "${ETCD_SNAPSHOT_URL}"
       managementType: Managed

3. Ensure that the secret that you referenced from the spec.secretEncryption.aescbc value contains the same AES key that you saved in the previous steps.

1. On management cluster 1, which you can think of as the source management cluster, the control plane and workers interact by using the external DNS API. The external DNS API is accessible, and a load balancer sits between the management clusters.

   

2. You take a snapshot of the hosted cluster, which includes etcd, the control plane, and the worker nodes. During this process, the worker nodes continue to try to access the external DNS API even if it is not accessible, the workloads are running, the control plane is saved in a local manifest file, and etcd is backed up to an S3 bucket. The data plane is active and the control plane is paused.

   

3. On management cluster 2, which you can think of as the destination management cluster, you restore etcd from the S3 bucket and restore the control plane from the local manifest file. During this process, the external DNS API is stopped, the hosted cluster API becomes inaccessible, and any workers that use the API are unable to update their manifest files, but the workloads are still running.

   

4. The external DNS API is accessible again, and the worker nodes use it to move to management cluster 2. The external DNS API can access the load balancer that points to the control plane.

   

5. On management cluster 2, the control plane and worker nodes interact by using the external DNS API. The resources are deleted from management cluster 1, except for the S3 backup of etcd. If you try to set up the hosted cluster again on mangagement cluster 1, it will not work.

   

Procedure

1. Create a configmap file to declare the source management cluster by entering this command:

   $ oc create configmap mgmt-parent-cluster -n default --from-literal=from=${MGMT_CLUSTER_NAME}

2. Shut down the reconciliation in the hosted cluster and in the node pools by entering these commands:

   PAUSED_UNTIL="true"
   oc patch -n ${HC_CLUSTER_NS} hostedclusters/${HC_CLUSTER_NAME} -p '{"spec":{"pausedUntil":"'${PAUSED_UNTIL}'"}}' --type=merge
   oc scale deployment -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --replicas=0 kube-apiserver openshift-apiserver openshift-oauth-apiserver control-plane-operator

   PAUSED_UNTIL="true"
   oc patch -n ${HC_CLUSTER_NS} hostedclusters/${HC_CLUSTER_NAME} -p '{"spec":{"pausedUntil":"'${PAUSED_UNTIL}'"}}' --type=merge
   oc patch -n ${HC_CLUSTER_NS} nodepools/${NODEPOOLS} -p '{"spec":{"pausedUntil":"'${PAUSED_UNTIL}'"}}' --type=merge
   oc scale deployment -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --replicas=0 kube-apiserver openshift-apiserver openshift-oauth-apiserver control-plane-operator

3. Back up etcd and upload the data to an S3 bucket by running this bash script:

   Tip

   Wrap this script in a function and call it from the main function.

   # ETCD Backup
   ETCD_PODS="etcd-0"
   if [ "${CONTROL_PLANE_AVAILABILITY_POLICY}" = "HighlyAvailable" ]; then
     ETCD_PODS="etcd-0 etcd-1 etcd-2"
   fi
   
   for POD in ${ETCD_PODS}; do
     # Create an etcd snapshot
     oc exec -it ${POD} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -- env ETCDCTL_API=3 /usr/bin/etcdctl --cacert /etc/etcd/tls/client/etcd-client-ca.crt --cert /etc/etcd/tls/client/etcd-client.crt --key /etc/etcd/tls/client/etcd-client.key --endpoints=localhost:2379 snapshot save /var/lib/data/snapshot.db
     oc exec -it ${POD} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -- env ETCDCTL_API=3 /usr/bin/etcdctl -w table snapshot status /var/lib/data/snapshot.db
   
     FILEPATH="/${BUCKET_NAME}/${HC_CLUSTER_NAME}-${POD}-snapshot.db"
     CONTENT_TYPE="application/x-compressed-tar"
     DATE_VALUE=`date -R`
     SIGNATURE_STRING="PUT\n\n${CONTENT_TYPE}\n${DATE_VALUE}\n${FILEPATH}"
   
     set +x
     ACCESS_KEY=$(grep aws_access_key_id ${AWS_CREDS} | head -n1 | cut -d= -f2 | sed "s/ //g")
     SECRET_KEY=$(grep aws_secret_access_key ${AWS_CREDS} | head -n1 | cut -d= -f2 | sed "s/ //g")
     SIGNATURE_HASH=$(echo -en ${SIGNATURE_STRING} | openssl sha1 -hmac "${SECRET_KEY}" -binary | base64)
     set -x
   
     # FIXME: this is pushing to the OIDC bucket
     oc exec -it etcd-0 -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -- curl -X PUT -T "/var/lib/data/snapshot.db" \
       -H "Host: ${BUCKET_NAME}.s3.amazonaws.com" \
       -H "Date: ${DATE_VALUE}" \
       -H "Content-Type: ${CONTENT_TYPE}" \
       -H "Authorization: AWS ${ACCESS_KEY}:${SIGNATURE_HASH}" \
       https://${BUCKET_NAME}.s3.amazonaws.com/${HC_CLUSTER_NAME}-${POD}-snapshot.db
   done

   For more information about backing up etcd, see "Backing up and restoring etcd on a hosted cluster".

4. Back up Kubernetes and OpenShift Container Platform objects by entering the following commands. You need to back up the following objects:

   • HostedCluster and NodePool objects from the HostedCluster namespace
   • HostedCluster secrets from the HostedCluster namespace
   • HostedControlPlane from the Hosted Control Plane namespace
   • Cluster from the Hosted Control Plane namespace
   • AWSCluster, AWSMachineTemplate, and AWSMachine from the Hosted Control Plane namespace
   • MachineDeployments, MachineSets, and Machines from the Hosted Control Plane namespace

   • ControlPlane secrets from the Hosted Control Plane namespace

     mkdir -p ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS} ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}
     chmod 700 ${BACKUP_DIR}/namespaces/
     
     # HostedCluster
     echo "Backing Up HostedCluster Objects:"
     oc get hc ${HC_CLUSTER_NAME} -n ${HC_CLUSTER_NS} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/hc-${HC_CLUSTER_NAME}.yaml
     echo "--> HostedCluster"
     sed -i '' -e '/^status:$/,$d' ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/hc-${HC_CLUSTER_NAME}.yaml
     
     # NodePool
     oc get np ${NODEPOOLS} -n ${HC_CLUSTER_NS} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/np-${NODEPOOLS}.yaml
     echo "--> NodePool"
     sed -i '' -e '/^status:$/,$ d' ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/np-${NODEPOOLS}.yaml
     
     # Secrets in the HC Namespace
     echo "--> HostedCluster Secrets:"
     for s in $(oc get secret -n ${HC_CLUSTER_NS} | grep "^${HC_CLUSTER_NAME}" | awk '{print $1}'); do
         oc get secret -n ${HC_CLUSTER_NS} $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/secret-${s}.yaml
     done
     
     # Secrets in the HC Control Plane Namespace
     echo "--> HostedCluster ControlPlane Secrets:"
     for s in $(oc get secret -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} | egrep -v "docker|service-account-token|oauth-openshift|NAME|token-${HC_CLUSTER_NAME}" | awk '{print $1}'); do
         oc get secret -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/secret-${s}.yaml
     done
     
     # Hosted Control Plane
     echo "--> HostedControlPlane:"
     oc get hcp ${HC_CLUSTER_NAME} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/hcp-${HC_CLUSTER_NAME}.yaml
     
     # Cluster
     echo "--> Cluster:"
     CL_NAME=$(oc get hcp ${HC_CLUSTER_NAME} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o jsonpath={.metadata.labels.\*} | grep ${HC_CLUSTER_NAME})
     oc get cluster ${CL_NAME} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/cl-${HC_CLUSTER_NAME}.yaml
     
     # AWS Cluster
     echo "--> AWS Cluster:"
     oc get awscluster ${HC_CLUSTER_NAME} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awscl-${HC_CLUSTER_NAME}.yaml
     
     # AWS MachineTemplate
     echo "--> AWS Machine Template:"
     oc get awsmachinetemplate ${NODEPOOLS} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awsmt-${HC_CLUSTER_NAME}.yaml
     
     # AWS Machines
     echo "--> AWS Machine:"
     CL_NAME=$(oc get hcp ${HC_CLUSTER_NAME} -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o jsonpath={.metadata.labels.\*} | grep ${HC_CLUSTER_NAME})
     for s in $(oc get awsmachines -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --no-headers | grep ${CL_NAME} | cut -f1 -d\ ); do
         oc get -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} awsmachines $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awsm-${s}.yaml
     done
     
     # MachineDeployments
     echo "--> HostedCluster MachineDeployments:"
     for s in $(oc get machinedeployment -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name); do
         mdp_name=$(echo ${s} | cut -f 2 -d /)
         oc get -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machinedeployment-${mdp_name}.yaml
     done
     
     # MachineSets
     echo "--> HostedCluster MachineSets:"
     for s in $(oc get machineset -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name); do
         ms_name=$(echo ${s} | cut -f 2 -d /)
         oc get -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machineset-${ms_name}.yaml
     done
     
     # Machines
     echo "--> HostedCluster Machine:"
     for s in $(oc get machine -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name); do
         m_name=$(echo ${s} | cut -f 2 -d /)
         oc get -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} $s -o yaml > ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machine-${m_name}.yaml
     done

5. Clean up the ControlPlane routes by entering this command:

   $ oc delete routes -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --all

   By entering that command, you enable the ExternalDNS Operator to delete the Route53 entries.

6. Verify that the Route53 entries are clean by running this script:

   function clean_routes() {
   
       if [[ -z "${1}" ]];then
           echo "Give me the NS where to clean the routes"
           exit 1
       fi
   
       # Constants
       if [[ -z "${2}" ]];then
           echo "Give me the Route53 zone ID"
           exit 1
       fi
   
       ZONE_ID=${2}
       ROUTES=10
       timeout=40
       count=0
   
       # This allows us to remove the ownership in the AWS for the API route
       oc delete route -n ${1} --all
   
       while [ ${ROUTES} -gt 2 ]
       do
           echo "Waiting for ExternalDNS Operator to clean the DNS Records in AWS Route53 where the zone id is: ${ZONE_ID}..."
           echo "Try: (${count}/${timeout})"
           sleep 10
           if [[ $count -eq timeout ]];then
               echo "Timeout waiting for cleaning the Route53 DNS records"
               exit 1
           fi
           count=$((count+1))
           ROUTES=$(aws route53 list-resource-record-sets --hosted-zone-id ${ZONE_ID} --max-items 10000 --output json | grep -c ${EXTERNAL_DNS_DOMAIN})
       done
   }
   
   # SAMPLE: clean_routes "<HC ControlPlane Namespace>" "<AWS_ZONE_ID>"
   clean_routes "${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}" "${AWS_ZONE_ID}"

Procedure

1. Verify that the new management cluster does not contain any namespaces from the cluster that you are restoring by entering these commands:

   # Just in case
   export KUBECONFIG=${MGMT2_KUBECONFIG}
   BACKUP_DIR=${HC_CLUSTER_DIR}/backup
   
   # Namespace deletion in the destination Management cluster
   $ oc delete ns ${HC_CLUSTER_NS} || true
   $ oc delete ns ${HC_CLUSTER_NS}-{HC_CLUSTER_NAME} || true

2. Re-create the deleted namespaces by entering these commands:

   # Namespace creation
   $ oc new-project ${HC_CLUSTER_NS}
   $ oc new-project ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}

3. Restore the secrets in the HC namespace by entering this command:

   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/secret-*

4. Restore the objects in the HostedCluster control plane namespace by entering these commands:

   # Secrets
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/secret-*
   
   # Cluster
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/hcp-*
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/cl-*

5. If you are recovering the nodes and the node pool to reuse AWS instances, restore the objects in the HC control plane namespace by entering these commands:

   # AWS
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awscl-*
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awsmt-*
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/awsm-*
   
   # Machines
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machinedeployment-*
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machineset-*
   $ oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}-${HC_CLUSTER_NAME}/machine-*

6. Restore the etcd data and the hosted cluster by running this bash script:

   ETCD_PODS="etcd-0"
   if [ "${CONTROL_PLANE_AVAILABILITY_POLICY}" = "HighlyAvailable" ]; then
     ETCD_PODS="etcd-0 etcd-1 etcd-2"
   fi
   
   HC_RESTORE_FILE=${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/hc-${HC_CLUSTER_NAME}-restore.yaml
   HC_BACKUP_FILE=${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/hc-${HC_CLUSTER_NAME}.yaml
   HC_NEW_FILE=${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/hc-${HC_CLUSTER_NAME}-new.yaml
   cat ${HC_BACKUP_FILE} > ${HC_NEW_FILE}
   cat > ${HC_RESTORE_FILE} <<EOF
       restoreSnapshotURL:
   EOF
   
   for POD in ${ETCD_PODS}; do
     # Create a pre-signed URL for the etcd snapshot
     ETCD_SNAPSHOT="s3://${BUCKET_NAME}/${HC_CLUSTER_NAME}-${POD}-snapshot.db"
     ETCD_SNAPSHOT_URL=$(AWS_DEFAULT_REGION=${MGMT2_REGION} aws s3 presign ${ETCD_SNAPSHOT})
   
     # FIXME no CLI support for restoreSnapshotURL yet
     cat >> ${HC_RESTORE_FILE} <<EOF
       - "${ETCD_SNAPSHOT_URL}"
   EOF
   done
   
   cat ${HC_RESTORE_FILE}
   
   if ! grep ${HC_CLUSTER_NAME}-snapshot.db ${HC_NEW_FILE}; then
     sed -i '' -e "/type: PersistentVolume/r ${HC_RESTORE_FILE}" ${HC_NEW_FILE}
     sed -i '' -e '/pausedUntil:/d' ${HC_NEW_FILE}
   fi
   
   HC=$(oc get hc -n ${HC_CLUSTER_NS} ${HC_CLUSTER_NAME} -o name || true)
   if [[ ${HC} == "" ]];then
       echo "Deploying HC Cluster: ${HC_CLUSTER_NAME} in ${HC_CLUSTER_NS} namespace"
       oc apply -f ${HC_NEW_FILE}
   else
       echo "HC Cluster ${HC_CLUSTER_NAME} already exists, avoiding step"
   fi

7. If you are recovering the nodes and the node pool to reuse AWS instances, restore the node pool by entering this command:

   oc apply -f ${BACKUP_DIR}/namespaces/${HC_CLUSTER_NS}/np-*

Procedure

1. Scale the deployment and statefulset objects by entering these commands:

   Important

   Do not scale the stateful set if the value of its spec.persistentVolumeClaimRetentionPolicy.whenScaled field is set to Delete, because this could lead to a loss of data.

   As a workaround, update the value of the spec.persistentVolumeClaimRetentionPolicy.whenScaled field to Retain. Ensure that no controllers exist that reconcile the stateful set and would return the value back to Delete, which could lead to a loss of data.

   # Just in case
   export KUBECONFIG=${MGMT_KUBECONFIG}
   
   # Scale down deployments
   oc scale deployment -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --replicas=0 --all
   oc scale statefulset.apps -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --replicas=0 --all
   sleep 15

2. Delete the NodePool objects by entering these commands:

   NODEPOOLS=$(oc get nodepools -n ${HC_CLUSTER_NS} -o=jsonpath='{.items[?(@.spec.clusterName=="'${HC_CLUSTER_NAME}'")].metadata.name}')
   if [[ ! -z "${NODEPOOLS}" ]];then
       oc patch -n "${HC_CLUSTER_NS}" nodepool ${NODEPOOLS} --type=json --patch='[ { "op":"remove", "path": "/metadata/finalizers" }]'
       oc delete np -n ${HC_CLUSTER_NS} ${NODEPOOLS}
   fi

3. Delete the machine and machineset objects by entering these commands:

   # Machines
   for m in $(oc get machines -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name); do
       oc patch -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} ${m} --type=json --patch='[ { "op":"remove", "path": "/metadata/finalizers" }]' || true
       oc delete -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} ${m} || true
   done
   
   oc delete machineset -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --all || true

4. Delete the cluster object by entering these commands:

   # Cluster
   C_NAME=$(oc get cluster -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name)
   oc patch -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} ${C_NAME} --type=json --patch='[ { "op":"remove", "path": "/metadata/finalizers" }]'
   oc delete cluster.cluster.x-k8s.io -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --all

5. Delete the AWS machines (Kubernetes objects) by entering these commands. Do not worry about deleting the real AWS machines. The cloud instances will not be affected.

   # AWS Machines
   for m in $(oc get awsmachine.infrastructure.cluster.x-k8s.io -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} -o name)
   do
       oc patch -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} ${m} --type=json --patch='[ { "op":"remove", "path": "/metadata/finalizers" }]' || true
       oc delete -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} ${m} || true
   done

6. Delete the HostedControlPlane and ControlPlane HC namespace objects by entering these commands:

   # Delete HCP and ControlPlane HC NS
   oc patch -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} hostedcontrolplane.hypershift.openshift.io ${HC_CLUSTER_NAME} --type=json --patch='[ { "op":"remove", "path": "/metadata/finalizers" }]'
   oc delete hostedcontrolplane.hypershift.openshift.io -n ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} --all
   oc delete ns ${HC_CLUSTER_NS}-${HC_CLUSTER_NAME} || true

7. Delete the HostedCluster and HC namespace objects by entering these commands:

   # Delete HC and HC Namespace
   oc -n ${HC_CLUSTER_NS} patch hostedclusters ${HC_CLUSTER_NAME} -p '{"metadata":{"finalizers":null}}' --type merge || true
   oc delete hc -n ${HC_CLUSTER_NS} ${HC_CLUSTER_NAME}  || true
   oc delete ns ${HC_CLUSTER_NS} || true

1. Load the KUBECONFIG environment variable with the hosted cluster’s kubeconfig path.

2. Enter this command:

   $ oc delete pod -n openshift-ovn-kubernetes --all