IBM Power 720 Overview page 154

System requirements for source and destination
The source partition must be one that has only virtual devices. If there are any physical
devices in its allocation, they must be removed before the validation or migration is initiated.
An N_Port ID Virtualization (NPIV) device is considered virtual and is compatible with
partition migration.
The hypervisor must support the Partition Mobility functionality (also called migration process)
that is available on POWER6, POWER6+, POWER7 and POWER7+ processor-based
hypervisors. Firmware must be at firmware level eFW3.2 or later. All POWER7+
processor-based hypervisors support Live Partition Mobility. Source and destination systems
can have separate firmware levels, but they must be compatible with each other.
A possibility is to migrate partitions back and forth between POWER6, POWER6+, POWER7
and POWER7+ processor-based servers. Partition Mobility uses the POWER6 or POWER6+
Compatibility Modes that are provided by POWER7 and POWER7+ processor-based servers.
On the POWER7+ processor-based server, the migrated partition is then executing in
POWER6 or POWER6+ Compatibility Mode.
Support of both processors: Because POWER7 and POWER7+ use the same
Instruction Set Architecture (ISA), they are equivalent regarding partition mobility, that is
POWER7 Compatibility Mode supports both POWER7 and POWER7+ processors.
If you want to move an active logical partition from a POWER6 processor-based server to a
POWER7+ processor-based server so that the logical partition can take advantage of the
additional capabilities available with the POWER7+ processor, use the following steps:
1. Set the partition-preferred processor compatibility mode to the default mode. When you
activate the logical partition on the POWER6 or POWER6+ processor-based server, it
runs in the POWER6 or POWER6+ mode.
2. Move the logical partition to the POWER7+ processor-based server. Both the current
and preferred modes remain unchanged for the logical partition until you restart the
logical partition.
3. Restart the logical partition on the POWER7+ processor-based server. The hypervisor
evaluates the configuration. Because the preferred mode is set to default and the logical
partition now runs on a POWER7+ processor-based server, the highest mode available is
the POWER7+ mode. The hypervisor determines that the most fully featured mode that is
supported by the operating environment installed in the logical partition is the POWER7
mode and changes the current mode of the logical partition to the POWER7 mode.
Now the current processor compatibility mode of the logical partition is the POWER7 mode,
and the logical partition run on the POWER7+ processor-based server.
Tip: The following web page offers presentations of the supported migrations:
http://pic.dhe.ibm.com/infocenter/powersys/v3r1m5/index.jsp?topic=/p7hc3/iphc3p
cmcombosact.htm
The Virtual I/O Server on the source system provides the access to the client resources and
must be identified as a mover service partition (MSP). The Virtual Asynchronous Services
Interface (VASI) device allows the mover service partition to communicate with the hypervisor.
It is created and managed automatically by the managed console and will be configured on
both the source and destination Virtual I/O Servers, which are designated as the mover
service partitions for the mobile partition, to participate in active mobility. Other requirements
include a similar time-of-day on each server, systems must not be running on battery power,
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IBM Power 720 and 740 Technical Overview and Introduction