Managing HP Serviceguard A.11.20.20 for Linux, March 2014

your cluster without having to bring it down, you need to plan the initial configuration carefully.
Use the following guidelines:
• Set the Maximum Configured Packages parameter (described later in this chapter under
“Cluster Configuration Planning ” (page 86)) high enough to accommodate the additional
packages you plan to add.
• Networks should be pre-configured into the cluster configuration if they will be needed for
packages you will add later while the cluster is running. See “LAN Information ” (page 81).
See Chapter 7: “Cluster and Package Maintenance” (page 199), for more information about
changing the cluster configuration dynamically, that is, while the cluster is running.
4.2 Using Serviceguard with Virtual Machines
This section describes the various configurations for Serviceguard for Linux clusters using physical
machine, VMware virtual machines running on ESX server, and Kernel-based Virtual Machine
(KVM) guests built on KVM hypervisor provided with Red Hat Enterprise Linux 6 so as to provide
high availability for applications.
Serviceguard for Linux supports using VMWare and KVM guests as cluster nodes. In this
configuration, the virtual machine is a member of a Serviceguard cluster, allowing failover of
application packages between other physical or VM nodes in the cluster.
Running Serviceguard for Linux in the virtual machines provides a significant level of extra protection.
Serviceguard fails over an application when one or more number of failures occur, including:
• Failure of the application
• Failure of networking required by the application
• Failure of storage
• An operating system “hang” or the failure of virtual machine itself
• Failure of the physical machine
In addition, it provides the following advantages:
• Minimize both planned and unplanned downtime of VM guests
• Serviceguard for Linux rolling upgrade feature allows for less planned downtime
4.2.1 Rules and Restrictions
Using VMware guests as cluster nodes
• HP recommends that you configure the node using NPIV to have more than one guests from
each host as cluster.
Using KVM guests as cluster nodes
• The iSCSI is the only supported storage mechanism for shared storage in a KVM environment.
FibreChannel storage is not supported.
• Lock LUN is not supported on iSCSI storage device. Hence, Quorum server is the only supported
quorum mechanism that can be used for arbitration.
• Live migration of KVM guests is not supported when the KVM guests are configured as
Serviceguard cluster nodes.
• Serviceguard does not support KVM guests running on Red Hat Enterprise Virtualization
Hypervisor (RHEV) as cluster nodes.
80 Planning and Documenting an HA Cluster