In today’s digital era, workload mobility plays a vital role in supporting high availability, agility and uninterrupted services. In an IBM FlashSystem grid environment, a storage partition can seamlessly migrate from one system to another, along with its associated objects such as hosts, volumes, and volume groups.
Users can configure Policy Based Host Attach (PBHA) between any two systems in the grid. In both storage partition migration and PBHA scenarios, it is expected that ecosystem plugins—such as SVC GUI, Cinder, and vSphere plugins—continue to access the FlashSystem objects associated with a given storage partition, without interruption.
However, disruptions can occur during storage partition movement or in the event of a site failure, when the High Availability (HA) partner takes over. To address this, IBM FlashSystem introduces Orchestrated Management IP Mobility—a feature that ensures a unique partition IP address is assigned to each storage partition. This IP remains available regardless of the system on which the storage partition is activated, ensuring uninterrupted access by external tools.

Architecture: Orchestrate Partition IP Mobility:

The native orchestrator in IBM FlashSystem automates IP management based on use cases such as partition migration and PBHA. Its role includes:

•  Activating the partition IP on the non-AMS (Active Management System) site upon detection of site failure.
•  Unconfiguring the partition IP from the system when a storage partition is migrated to a new system.
• User can create upto 32 partition IP per system.

This intelligent IP mobility mechanism provides seamless management during movement or failover scenarios.

Management Portset Mapping to Storage Partitions:

•  The management portset is created on the AMS site.
• An IP address is then assigned to this portset which called as a management IP.
•  The portset can be mapped to an existing storage partition or during the creation of a new partition. The IP associated with it addressed as a partition IP.
• Once an HA policy is applied, the portset and its IP are automatically reflected on the non-AMS site along with all associated metadata.

Unmapping Management Portsets:

•  Unmapping a management portset from a storage partition must be initiated from the AMS site.
•  Upon unmapping, the portset and associated IP are removed from both the AMS and non-AMS sites.
• The partition IP will be visible again on the non-AMS site only if the user remaps the portset to the respective storage partition.

Handling Portsets During HA Policy Assignment:

When a HA replication policy is assigned to a storage partition:

•  The partition, along with its associated management portset and  IP address, is replicated to the non-AMS site.
• This ensures the storage partition is always accessible via its dedicated partition IP.
•  If the HA policy is removed, the partition, portset, and associated partition IP are also removed from the non-AMS site.

Handling Portsets During Partition Migration:

•  Users can initiate migration of a storage partition from an AMS site to a non-AMS site.
•  After all partition objects are transferred to the target system, the source partition is deleted.
• The management portset associated with the source must also be deleted from both AMS and non-AMS sites to maintain configuration integrity.

Summary:

Enhancements in non-disruptive storage partition migration and PBHA technology within the FlashSystem grid significantly improve usability by automating complex tasks and introducing intelligent features like Orchestrated Management IP Mobility. These advancements deliver a smooth, efficient data mobility experience and help users maintain continuity, even in the face of system transitions or failures.

Reference Material:

• Creating a portset: https://ibmdocs-test.dcs.ibm.com/docs/en/flashsystem_reviews_910_test?topic=portsets-creating-portset
• Mapping partition with management portset: https://ibmdocs-test.dcs.ibm.com/docs/en/flashsystem_reviews_910_test?topic=commands-mkpartition
•  Changing partition configuration: https://ibmdocs-test.dcs.ibm.com/docs/en/flashsystem_reviews_910_test?topic=commands-chpartition