Edit: Still something to consider.
Originally posted November 27, 2018 on AIXchange
A sound disaster recovery plan is one that’s regularly being updated. With this in mind, I want to cite this overview of Geographically Dispersed Resiliency (GDR), a DR option that is designed for efficiency.
The GDR solution provides a highly available environment by identifying a set of resources that are required for processing the virtual machines in a server during disaster situations.
The GDR solution uses the following subsystems:
Controller system (KSYS)
Site
Host
Virtual machines (VMs) or logical partitions (LPARs)
Storage
Network
Hardware Management Console (HMC)
Virtual I/O Server (VIOS)
IBM Support also has a comparison of PowerHA and GDR:
Disaster recovery of applications and services is a key component to provide continuous business services. The Geographically Dispersed Resiliency for Power Systems (GDR) solution is a disaster recovery solution that is easy to deploy and provides automated operations to recover the production site. The GDR solution is based on the Geographically Dispersed Parallel Sysplex (GDPS) offering concepts that optimizes the usage of resources. This solution does not require you to deploy the backup virtual machines (VMs) for disaster recovery. Thus, the GDR solution reduces the software license and administrative costs.
The following high availability (HA) and disaster recovery (DR) models are commonly used by customers:
Cluster-based technology
VM restart-based technology
Clustered HA and DR solutions typically deploy redundant hardware and software components to provide near real-time failover when one or more components fail. The VM restart-based HA and DR solution relies on an out-of-band monitoring and management component that restarts the virtual machines on other hardware when the host infrastructure fails. The GDR solution is based on the VM restart technology.
The following table identifies the differences between the conventional cluster-based disaster recovery model and the GDR solution:
A disaster recovery implementation that uses a set of scripts and manual processes at a site level might take more time to recover and restore the services. The GDR solution automates the operations to recover your production site. This solution provides an easy deployment model that uses a controller system (KSYS) to monitor the entire virtual machine (VM) environment. This solution also provides flexible failover policies and storage replication management.
Finally, Michael Herrera has some great videos that cover concepts, software and advanced features.
As you design and update your DR solutions, be sure to consider GDR.