The IBM i PowerHA product portfolio has several additional enhancements for environments on-premise, in the cloud, or in hybrid or multi-cloud environments. These enhancements include:

• Greater flexibility and availability in Geographic Mirroring environments with multi-target Geographic Mirroring allowing replication between up to six nodes.

• Simplified hardware upgrades with reduced impact on the production workload using multi-target Geographic Mirroring.

• Increased agility and adaptability in Geographic Mirroring environments with the ability to change Geographic Mirroring parameters with minimal impact on the production workload.

• Simplified recoverability in Geographic Mirroring environments with the ability to detach and vary on suspended copies of the IASP.

• Continued enhancements to the PowerHA modern web interface.

Geographic Mirroring

PowerHA Geographic Mirroring replicates independent auxiliary storage pool (IASP) via IBM i networking. As the system writes data from main memory to disk, the same data is sent over TCP/IP to the target system to be written to disk, ensuring identical data between both systems. As a result, geographic Mirroring provides the same simplicity as SAN-based replication, with the flexibility to work with any storage (internal or external), and is highly efficient.

The following enhancements extend PowerHA’s Geographic Mirroring by providing greater flexibility and improved availability.

Multi-target Geographic Mirroring

Previously, Geographic Mirroring was limited to two nodes: source and target. While many combine Geographic Mirroring with other technologies, including LUN-Level Switching and FlashCopy, those technologies require SAN-based storage.

Geographic Mirroring now supports replication between up to six cluster nodes while keeping the same management simplicity as environments with only two nodes. These enhancements enable the following:

• Greater flexibility for additional Geographic Mirroring replication topologies including on-premise, hybrid-cloud, and cloud environments. For example, having production and HA systems on-premise and a disaster recovery system in the cloud.

• With added flexibility for additional copies of the IASP, it is now possible to use Db2 Mirror with PowerHA and internal storage where the environment has a Db2 Mirror pair at the production site and a Db2 Mirror pair at the DR site.

• Simplified hardware upgrades with reduced impact to the production workload. Previously, hardware upgrades in a Geographic Mirroring environment required varying off the production copy of the IASP both for deconfiguring and reconfiguring replication. With this enhancement, the production copy of the IASP can remain online during CFGGEOMIR operations of additional copies of the IASP, significantly reducing the impact on production workloads for hardware migrations.

• With the ability to replicate data between more than two nodes, it is now possible to protect your Recovery Point Objective (RPO) during save operations by using an additional node for offline save operations while the HA or DR systems continue to receive changes from the production system.

Reduced Impact on Production for Changing Geographic Mirroring Parameters

This enhancement enables changing parameters such as synchronous or asynchronous communication, without needing to vary off the production copy of the IASP. This enhancement significantly increases the ability for a geographic mirroring configuration to change and adapt without impacting the production workload. The following parameters can now be changed using the Change ASP Session (CHGASPSSN) command while the production copy is online: transmission delivery, transmission compression, synchronization priority, and suspend timeout.

Simplified Recoverability with the Ability to Detach Suspended Copies of the IASP

In a Geographic Mirroring environment, when replication is suspended it is possible to fail over to a usable back-level copy. This enhancement improves the usability in these environments by allowing a Change ASP Session (CHGASPSSN) with option *DETACH on a suspended copy of the IASP. This enables operations, including easy verification of the back-level copy of the IASP or the ability to perform a save operation from the target, even when replication is suspended without needing a to perform a failover.

PowerHA Modern Web Interface Enhancements

The new PowerHA web interface is available as of December 2022. This enhancement extends the web interface with additional monitoring capabilities, including the ability to see additional information on monitored resources in the administrative domain.

Enhancement Availability