HSM KMS High Availability Backup and Recovery
When running the HSM KMS in high availability mode, if either of the two nodes fails, a role instance can be assigned to another node and federated into the service by the single remaining active node. In other words, you can bring a node that is part of the cluster, but that is not running HSM KMS role instances, into the service by making it an HSM KMS role instance–more specifically, an HSM KMS proxy role instance and an HSM KMS metastore role instance. So each node acts as an online ("hot" backup) backup of the other. In many cases, this will be sufficient. However, if a manual ("cold" backup) backup of the files necessary to restore the service from scratch is desirable, you can create that as well.
To create a backup, copy the /var/lib/hsmkp and /var/lib/hsmkp-meta directories on one or more of the nodes running HSM KMS role instances.
To restore from a backup: bring up a completely new instance of the HSM KMS service, and copy the /var/lib/hsmkp and /var/lib/hsmkp-meta directories from the backup onto the file system of the restored nodes before starting HSM KMS for the first time.