With LPM, you can move a running LPAR from one system to another one without disruption. Inactive partition mobility allows you to move a powered-off LPAR from one system to another one.
LPM provides systems management flexibility and improves system availability by avoiding the following situations:
Ê Planned outages for hardware upgrade or firmware maintenance.
Ê Unplanned downtime. With preventive failure management, if a server indicates a potential failure, you can move its LPARs to another server before the failure occurs.
For more information and requirements for LPM, see IBM PowerVM Live Partition Mobility, SG24-7460.
HMC 10.1.1020.0 and VIOS 3.1.3.21 or later provide the following enhancements to the LPM feature:
Ê Automatically choose fastest network for LPM memory transfer.
Ê Allow LPM when a virtual optical device is assigned to a partition.
5.1.5 Active Memory Mirroring
Active Memory Mirroring (AMM) for Hypervisor is available as an option (#EM8G) to enhance resilience by mirroring critical memory that is used by the PowerVM hypervisor so that it can continue operating in a memory failure.
A portion of available memory can be proactively partitioned such that a duplicate set can be used on non-correctable memory errors. This partition can be implemented at the granularity of DIMMs or logical memory blocks.
5.1.6 Remote Restart
Remote Restart is a high availability (HA) option for partitions. If an error occurs that causes a server outage, a partition that is configured for Remote Restart can be restarted on a different physical server. At times, it might take longer to start the server, in which case the Remote Restart function can be used for faster reprovisioning of the partition. Typically, this task can be done faster than restarting the server that stopped and then restarting the partitions. The Remote Restart function relies on technology that is like LPM, where a partition is configured with storage on a SAN that is shared (accessible) by the server that hosts the partition.
HMC 10R1 provides an enhancement to the Remote Restart feature that enables remote restart when a virtual optical device is assigned to a partition.
5.1.7 IBM Power processor modes
Although they are not virtualization features, the IBM Power processor modes are described here because they affect various virtualization features.
On IBM Power servers, partitions can be configured to run in several modes, including the following modes:
Ê Power8
This native mode for Power8 processors implements version 2.07 of the IBM Power instruction set architecture (ISA). For more information, see Processor compatibility mode definitions.
Ê Power9
This native mode for Power9 processors implements version 3.0 of the IBM Power ISA. For more information, see Processor compatibility mode definitions.
Ê Power10
This native mode for Power10 processors implements version 3.1 of the IBM Power ISA. For more information, see Processor compatibility mode definitions.
Figure 5-2 shows the available processor modes on a Power10 processor-based mid-range server.
Figure 5-2 Processor modes
Processor compatibility mode is important when LPM migration is planned between different generation of servers. An LPAR that might be migrated to a machine that is managed by a processor from another generation must be activated in a specific compatibility mode.
Note: Migrating an LPAR from a Power7 processor-based server to a Power10 processor-based mid-range server by using LPM is not supported; however, the following steps can be completed to accomplish this task:
1. Migrate LPAR from a Power7 processor-based server to a Power8 or Power9 processor-based server by using LPM.
2. Migrate the LPAR from the Power8 or Power9 processor-based server to a Power10 processor-based mid-range server.
The OS running on the Power7 processor-based server must be supported on the Power10 processor-based mid-range server or must be upgraded to a supported level before completing these steps.
5.1.8 Single-root I/O virtualization
Single-root I/O virtualization (SR-IOV) is an extension to the Peripheral Component Interconnect Express (PCIe) specification that allows multiple OSs to simultaneously share a PCIe adapter with little or no runtime involvement from a hypervisor or other virtualization intermediary.
SR-IOV is PCI standard architecture that enables PCIe adapters to become self-virtualizing. It enables adapter consolidation through sharing, much like logical partitioning enables server consolidation. With an adapter capable of SR-IOV, you can assign virtual slices of a single physical adapter to multiple partitions through logical ports, which is done without a VIOS.
5.1.9 More information about virtualization features
The following IBM Redbooks publications provide more information about the virtualization features:
Ê IBM PowerVM Best Practices, SG24-8062
Ê IBM PowerVM Virtualization Introduction and Configuration, SG24-7940
Ê IBM PowerVM Virtualization Managing and Monitoring, SG24-7590
Ê IBM Power Systems SR-IOV: Technical Overview and Introduction, REDP-5065