Veritas InfoScale™ for Kubernetes Environments 8.0.200 - Linux
- Overview
- System requirements
- Preparing to install InfoScale on Containers
- Installing Veritas InfoScale on OpenShift
- Introduction
- Prerequisites
- Additional Prerequisites for Azure RedHat OpenShift (ARO)
- Considerations for configuring cluster or adding nodes to an existing cluster
- Installing InfoScale on a system with Internet connectivity
- Installing InfoScale in an air gapped system
- Installing Veritas InfoScale on Kubernetes
- Introduction
- Prerequisites
- Installing the Special Resource Operator
- Tagging the InfoScale images on Kubernetes
- Applying licenses
- Tech Preview: Installing InfoScale on an Azure Kubernetes Service(AKS) cluster
- Considerations for configuring cluster or adding nodes to an existing cluster
- Installing InfoScale on Kubernetes
- Installing InfoScale by using the plugin
- Undeploying and uninstalling InfoScale
- Configuring KMS-based Encryption on an OpenShift cluster
- Configuring KMS-based Encryption on a Kubernetes cluster
- InfoScale CSI deployment in Container environment
- CSI plugin deployment
- Raw block volume support
- Static provisioning
- Dynamic provisioning
- Resizing Persistent Volumes (CSI volume expansion)
- Snapshot provisioning (Creating volume snapshots)
- Managing InfoScale volume snapshots with Velero
- Volume cloning
- Using InfoScale with non-root containers
- Using InfoScale in SELinux environments
- CSI Drivers
- Creating CSI Objects for OpenShift
- Installing and configuring InfoScale DR Manager on OpenShift
- Installing and configuring InfoScale DR Manager on Kubernetes
- Disaster Recovery scenarios
- Configuring InfoScale
- Administering InfoScale on Containers
- Upgrading InfoScale
- Troubleshooting
Takeover
You can initiate takeover on a secondary cluster when peer primary cluster is down or disconnected. This can be used in case of disaster when primary cluster abruptly goes down or is disconnected, and application stack is online on the primary cluster. To recover, you can initiate a takeover. Takeover must be initiated from the surviving target cluster(the secondary cluster) where you want to recover application instances. On the secondary cluster, you can run kubectl or oc edit/patch <NameofDRplan> and update Spec:Force and Spec:PrimaryCluster attributes. Spec:PrimaryCluster must be changed to current primary cluster details.
Spec:Force attribute is a part of the DisasterRecoveryPlan object. Whenever you initiate a takeover, Spec:Force must be set to true. After Spec:Force is set to true, do not edit DisasterRecoveryPlan object. As peer clusters are not connected, any changes in DisasterRecoveryPlan cannot be synchronized across all peer clusters. As soon as all clusters are connected, stale application instances on outdated primary cluster are removed. Spec:Force is also automatically reset to false when all clusters are connected, thus concluding takeover operations.
Following entities are updated during a takeover.
Application metadata : When a takeover is initiated on the target cluster, latest/recent snapshot of managed application's metadata from the primary cluster is tagged for restoration. This snapshot is used for restoring application stack.
Application data : For stateful applications, you must have configured DataReplication CR and updated
DisasterRecoveryPlan:Spec:DataReplicationPointeraccordingly. DataReplication CR manages replication of application data from the primary cluster to the peer clusters(source to target). When a takeover is initiated on the target cluster, the proposed primary cluster assumes 'Primary' role and is allowed read write on Volumes. When outdated primary cluster is connected, it joins as a 'Secondary' role.DNS end points : The DNS custom resource updates and monitors the mapping for
The host name to IPaddress (A, AAAA, or PTR record)
Alias to hostname or canonical name(CNAME)
When a takeover is initiated, the DNS resource records are updated appropriately
You can check intermediate transient states like BackupStatus, ScheduleStatus, RestoreStatus, and DataReplicationStatus attributes of the Disaster Recovery Plan during takeover. To check logs if migration is stuck, run kubectl/oc logs -f --tail=100 deployments.apps/infoscale-dr-manager -n infoscale-vtas. After migration is complete, these transient states are cleaned and Status:PrimaryCluster in DisasterRecoveryPlan is updated to the new primary.