Setting up an etcd store for HADR in Db2

You must set up an etcd store to enable automated failover in a Db2 High Availability Disaster Recovery (HADR) configuration on IBM Software Hub.

Db2 HADR supports automated failover by using a mechanism that is called Governor. Governor relies on an etcd key-value store to track HADR state information, such as the current leader (primary node). Automated failover is only supported between the primary and principal standby, so a single etcd endpoint must be shared between the two deployments.

Note: If you use the built-in etcd store with the etcd pod, create a network policy to allow communication from all deployments with the etcd pod. See Creating a network policy for built-in etcd for details.
Important: For production deployments, a three-node etcd topology is required.

If etcd is installed on the same OpenShift® cluster, it must not be colocated on the same worker nodes as the Db2 deployments. Use pod anti-affinity in the etcd deployment.

To set up an etcd store for HADR, choose from the following methods:
  • You can use an external etcd store that can be a cloud-provided service, which is deployed on the OpenShift cluster, or hosted on-premises.
  • Deploy etcd packaged with the Db2 installation.
  • Deploy etcd packaged by Bitnami for Db2.
  • Using the built-in Db2 etcd store (only nonproduction, single OpenShift cluster environments).