Using HP Serviceguard for Linux with VMware

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• Serviceguard for Linux rolling upgrade feature allows for less planned downtime.
o Using just VMware HA requires that the target virtual server be brought down for an
operating system upgrade. Similarly an application must usually be down while it is
upgraded.
o With Serviceguard for Linux, an application (packages) can be moved off a virtual
machine and restarted on another node in the cluster. The “empty” server can then
have its operating system or applications upgraded while those applications are still
available to users since they are running on other nodes.
Serviceguard for Linux, combined with VMware, can provide a lower-cost method of protecting
applications that would not normally be run on a virtual machine. Applications can be failed over
between physical servers and virtual servers on the same or different physical hosts. Databases and
other CPU or IO intensive applications typically do not run in virtualized environments. Generally
these applications are protected by running in an HA cluster on “physical” machines. Cost savings
and some additional reliability can be realized by combining physical and virtual machines in a
cluster. In some environments, this configuration provides better utilization of data center resources.
Users often configure clusters with one node as a “back-up” node. When there are multiple clusters,
the number of physical servers can be reduced since there is no need for dedicated ”back-up”
hardware for each cluster. One physical system hosts back-up nodes for multiple clusters as virtual
achines.
m
Scope
This document describes how to configure Serviceguard for Linux clusters using physical machines
and VMware virtual machines running on ESX server, so as to provide high availability for
applications. As new versions of ESX server or Linux distributions are certified, they will be listed in
the Serviceguard for Linux certification matrix: www.hp.com/info/sglx
-> Certification matrix.
Note: Serviceguard is certified on VMware ESX guests, not on ESX hosts, and provides
high availability for applications, not for the virtual machines themselves.
A reasonable expertise in the installation and configuration of ESX server on x86 platforms, and
familiarity with its capabilities and limitations, is assumed. This document explains how to deploy
and configure Serviceguard for Linux in this environment.
From the point of view of Serviceguard installation and configuration, no additional special
expertise is required. However, there can be issues with heartbeat links unless these are configured
properly. These issues are discussed in the section on NIC teaming
.
Note: Except as noted in this white paper, all the Serviceguard configuration options documented
in the Managing HP Serviceguard for Linux manual are supported for VMware guests, and all the
documented requirements apply. You can find the latest version of the manual (seventh edition or
later) at http://docs.hp.com
-> High Availability -> Serviceguard for Linux.
Virtual Machine configuration considerations
Refer to the VMware document Server Configuration Guide [3] for details on configuring virtual
machines. The resources to be allocated to virtual machines depend on the complexity of the
applications deployed on them. A virtual machine (VM) limits the total number of PCI devices to 6.
For other limitations, refer to the document Configuration Maximums for VMware Infrastructure 3 [4]
VMware documents describe how to manage performance in a virtual machine environment. How
many virtual machines you can deploy on a given server depends on the capacity of that server and
the resource requirements of the applications running on it.