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

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This configuration provides the most flexibility in meeting recovery time objectives (RTOs) for VM guests and
applications while efficiently consolidating systems on VM hosts. For example, to consolidate a system environment
consisting of Windows servers and mission-critical applications running on HP-UX servers, the Windows servers with
a lower RTO can be made highly available by running them as VM guests encapsulated within Serviceguard
packages. For mission-critical applications with a higher RTO, protect them with Serviceguard packages running
within HP-UX VM guests, all running together on a minimum number of VM hosts.
Note:
Different versions of Serviceguard can be used for either cluster as long as they
are listed as supported in the Integrity VM/Serviceguard support matrix.
When implementing this configuration, there is a possibility that a failure of all heartbeat links between both clusters
could cause the VM node cluster to fail depending on the timing in which the surviving nodes in each cluster achieves
quorum and which cluster reforms first. This failure scenario can be mitigated by:
• Having multiple redundant heartbeat networks for both clusters
• Using Serviceguard A.11.19 for both clusters and setting the MEMBER_TIMEOUT parameter on the VM as node
cluster to at least 1 second greater than the reported max_reformation_duration value of the VM host cluster (this value
can be determined by using the command “cmviewcl -v -f line | grep max_reformation_duration”)
Serviceguard and Online VM Guest Migration
Online VM Migration is an optional add-on capability, introduced with Integrity VM B.04.10 that enables a running
VM guest and its applications to be moved from one VM host to another without service interruption. Throughout the
migration, all VM guest I/O connections to storage and networks remain active. The primary benefits of Online VM
Migration include reduced downtime for planned maintenance activities on VM hosts and static workload balancing
between VM hosts. VM guests encapsulated within Serviceguard packages can also be migrated online, providing
the additional benefits of protection against unplanned VM host hardware and software failures. This protection is not
available during an online migration and the planned movement of workloads that cannot be migrated online due to
VM host hardware or software differences.
Online migration of VM guests and VM as Serviceguard package is supported starting with the Integrity VM B.04.10
release for HP-UX and Windows guests. An example of online migration of VM guests and VM as Serviceguard
package is shown in figure 13.
Note:
Online migration of VMs as Serviceguard nodes is not supported while
Serviceguard is running on the node. Online migration of VMs as Serviceguard
nodes is supported if Serviceguard on the VM guest node is halted before
performing the online migration.