Chapter 6. Premigration checklists
Chapter 6. Premigration checklists Before you migrate your application workloads with the Migration Toolkit for Containers (MTC), review the following checklists. 6.1. Cluster health checklist ❏ The clusters meet the minimum hardware requirements for the specific platform and installation method, for example, on bare metal . ❏ All MTC prerequisites are met. ❏ All nodes have an active OpenShift Container Platform subscription. ❏ You have verified node health . ❏ The identity provider is working. ❏ The migration network has a minimum throughput of 10 Gbps. ❏ The clusters have sufficient resources for migration. Note Clusters require additional memory, CPUs, and storage in order to run a migration on top of normal workloads. Actual resource requirements depend on the number of Kubernetes resources being migrated in a single migration plan. You must test migrations in a non-production environment in order to estimate the resource requirements. ❏ The etcd disk performance of the clusters has been checked with fio . 6.2. Source cluster checklist ❏ You have checked for persistent volumes (PVs) with abnormal configurations stuck in a Terminating state by running the following command: USD oc get pv ❏ You have checked for pods whose status is other than Running or Completed by running the following command: USD oc get pods --all-namespaces | egrep -v 'Running | Completed' ❏ You have checked for pods with a high restart count by running the following command: USD oc get pods --all-namespaces --field-selector=status.phase=Running \ -o json | jq '.items[]|select(any( .status.containerStatuses[]; \ .restartCount > 3))|.metadata.name' Even if the pods are in a Running state, a high restart count might indicate underlying problems. ❏ The cluster certificates are valid for the duration of the migration process. ❏ You have checked for pending certificate-signing requests by running the following command: USD oc get csr -A | grep pending -i ❏ The registry uses a recommended storage type . ❏ You can read and write images to the registry. ❏ The etcd cluster is healthy. ❏ The average API server response time on the source cluster is less than 50 ms. 6.3. Target cluster checklist ❏ The cluster has the correct network configuration and permissions to access external services, for example, databases, source code repositories, container image registries, and CI/CD tools. ❏ External applications and services that use services provided by the cluster have the correct network configuration and permissions to access the cluster. ❏ Internal container image dependencies are met. ❏ The target cluster and the replication repository have sufficient storage space.
oc get pv oc get pods --all-namespaces | egrep -v 'Running | Completed' oc get pods --all-namespaces --field-selector=status.phase=Running -o json | jq '.items[]|select(any( .status.containerStatuses[]; .restartCount > 3))|.metadata.name' oc get csr -A | grep pending -i