Designing High Availability Solutions with HP Serviceguard and HP Integrity Virtual Machines

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Serviceguard LANs using Accelerated Virtual I/O (AVIO) must be configured using AVIO-supported host physical
point attachment (PPA) network devices.
In VM as Serviceguard package configurations using AVIO network devices, the Serviceguard standby LANs must
use supported host physical point attachment (PPA) devices supported by AVIO to prevent a loss of network
connectivity that will occur if using non-supported devices, even if the standby LAN link is up. Additional information
on AVIO drivers can be found in the “HP Integrity virtual machines installation, configuration, and administration”
reference manual associated with the Integrity VM version being deployed.
With the benefit of using Integrity VM to consolidate applications from physical machines to VMs, the advantages of
implementing VM as Serviceguard package configurations include providing HA for:
• VM guests in case of a VM host failure
• Standalone and other applications not designed for use in clustered environments
VM as Serviceguard package configurations have the following limitations:
It is difficult to monitor applications within the VM guest prior to Serviceguard A.11.19, as custom monitoring must be
developed and implemented (see the “guest application monitoring” section below to see the features added in
A.11.19)
• Application failover times will be slower for VM guests as compared to clustered applications due to the additional
time required to startup the VM and boot-up the guest OS
Toolkits for integrating virtual machines into Serviceguard packages
There are two toolkits available which simplify the creation, monitoring, and management of Integrity VM guests as
Serviceguard packages, the Integrity VM Serviceguard toolkit and the HP Serviceguard toolkit for Integrity Virtual
servers (SG-IVS). See the following sections below for the details of the toolkits.
The Integrity VM Serviceguard toolkit
The Integrity VM Serviceguard toolkit has been included in the HP Integrity VM product beginning with the B.02.00
version. The documentation for this toolkit can be found in the HP Integrity virtual machines installation, configuration
and administration guide, available at:
www.hp.com/go/hpux-hpvm-docs. The toolkit provides two commands:
• hpvmsg_package—This command is used to take an existing Integrity VM guest configured on Serviceguard
cluster shared storage, and create a Serviceguard package which will start, stop, and monitor the VM guest. After
a VM guest has been packaged the VM guest can only be started and stopped using Serviceguard commands, the
HPVM commands hpvmstart and hpvmstop are disabled from starting and stopping the VM guest. If the VM guest’s
backing store is located on a volume manager that supports exclusively shared storage, such as LVM or VxVM, the
command will configure the activation of the volume manager in the generated package. If the VM guest’s backing
store is located on a volume manager that supports concurrently shared storage, such as Shared LVM (SLVM) the
command will configure the generated package to have a same node dependency on the multi-node package for
the volume group or mount point package.
• hpvmsg_move—This command is used to perform an online migration of VM guests in Serviceguard packages.
Note that online migration is only supported for VM guests running on concurrently shared storage, such as whole
disk backing stores, Shared LVM volume groups or CFS file systems.
Advantages of the Integrity VM Serviceguard toolkit:
• This toolkit can create both legacy and modular package formats.
• This toolkit can create packages using Integrity VM versions prior to B.04.30, which support VM guests running
Windows or Linux, in addition to HP-UX.
Disadvantages of the Integrity VM Serviceguard toolkit:
• This toolkit does not use Serviceguard package modules, so you cannot generate a package using the Serviceguard
cmmakepkg command. Additionally some online package configuration change features are not supported.
• This toolkit will no longer be included with Integrity VM versions beyond B.04.30.
• This toolkit does not support VM guest backing stores on NFS mount points.
• This toolkit will not be enhanced to take advantage of new Integrity VM or Serviceguard features.