HP Integrity Virtual Machines 4.3: Installation, Configuration, Administration

You might want to segregate guests to balance the workload on VM Hosts workloads. For
example, you might want to separate guests whose workloads peak simultaneously. Or, perhaps
you want to group workloads together that have similar special resource requirements. For
example, you would usually run your multi-threaded applications on a VM Host that has several
CPUs in order to maximize the effectiveness of multi-way virtual machines. Online VM Migration
enables a new level of workload-to-resource alignment flexibility and agility -- you can segregate
or combine your workloads as you wish, without any interruption in application availability.
The Online VM Migration feature enables you to optimize the physical resources being used by
running guests. You can conveniently "park" idle, near-idle, or just currently less-critical guest
workloads together on a smaller or less powerful machine. You can use the dynamic memory
feature to reduce the amount of memory in use by the guests and shrink CPU entitlements to
more tightly packed guests on a smaller VM Host.
Table 9-1 provides the supported online migration paths for HP-UX and OpenVMS guests:
Table 9-1 Online Forward Migration Paths
Supported Forward Migration PathIntegrity VM Version
Integrity VM V4.1 or Integrity VM V4.2Integrity VM V4.1
Integrity VM V4.2, Integrity VM V4.2.5, or Integrity VM4.3Integrity VM V 4.2
Integrity VM V4.2.5 or Integrity VM V4.3Integrity VM V4.2.5
Integrity VM V.3Integrity VM V4.3
Online migration among Integrity servers is limited by the processor architecture. Online migration
among servers with processor family 31 is supported regardless of the model number within the
family. Migration among servers with processor family 32 and model numbers 0 or 1 is supported.
Otherwise, online migration is supported among servers with identical processor family and
model number.
To check if a guest can be migrated to the target VM Host, use the hpvmmigrate -s option.
9.1.2 Reasons for Migrating Virtual Machines Offline
This sections lists reasons why you might want to migrate a virtual machine offline. For example:
• The guest might be stopped, so you need to move the configuration information offline.
• Migrating the virtual machine offline does not use the VM Host resources (like memory and
CPUs) on the source and target VM Hosts.
• The guest might have local storage, logical volumes or file-backed storage, which must be
copied to the target VM Host.
• The source and target VM Hosts might have different processor types that prevent online
migration.
• The source VM Host might be running a version of Integrity VM prior to Version 4.3, which
does not support Online VM Migration.
• You can offline migrate guests between different processor families.
Table 9-2 provides the migration path for offline migration:
Table 9-2 Offline Migration Paths
Supported Offline Migration Path (Forward or Backward)Integrity VM Version
Integrity VM V3.5Integrity VM V3.5
Integrity VMV4.0Integrity VM V4.0
Integrity VM V4.1 or laterIntegrity VM V4.1 or later
178 Migrating Virtual Machines