Encrypted Volume and File System v1.1 Administrator's Guide

C Using EVFS with Serviceguard
This chapter describes how to use EVFS with the HP Serviceguard product.
This chapter addresses the following topics:
• “EVFS and Serviceguard Overview” (page 153)
• “Configuration Overview” (page 155)
• “Step 1: Installing EVFS” (page 156)
• “Step 2: Creating the Serviceguard Storage Infrastructure” (page 157)
• “Step 3: Configuring EVFS on the Configuration Node” (page 159)
• “Step 4: Configuring EVFS Volumes on the Adoptive Nodes” (page 161)
• “Step 5: Configuring Serviceguard using Modular packages” (page 164)
• “Step 6: Configuring Serviceguard using Legacy packages” (page 167)
EVFS and Serviceguard Overview
A Serviceguard cluster is a networked group of HP 9000 or Integrity servers (host systems known
as nodes) with redundant hardware and software so that a single point of failure does not
significantly disrupt service. Application packages (individual HP-UX processes) can be grouped
together in failover packages. A failover package runs on a single node at a time. The node on
which the package initially runs is the primary node. If a single service, node, network or other
resource fails, Serviceguard can automatically transfer, or fail over, control of the package to
another node within the cluster, referred to as the adoptive node.
Serviceguard supports special storage infrastructures for clusters, including cluster aware LVM
and VxVM volume groups. A cluster aware LVM volume group can be activated by nodes in
exclusive mode only. A cluster aware volume group is typically configured on a disk that is
physically connected to multiple nodes. This enables the volume group to be physically accessible
from multiple nodes but activated for exclusive write access by only one node at a time. When
used with failover packages, the volume group is activated for exclusive write access on the node
on which the package is running.
Serviceguard A.11.18 has a simpler package configuration method which allows smaller modules
to be built into packages. This eliminates the use of a separate package control script and needing
to manually distribute it. These packages are referred to as modular packages. Packages produced
by older versions of Serviceguard (versions A.11.16 or A.11.17) are referred to as legacy packages.
You can use EVFS volumes with Serviceguard failover packages as follows:
• Serviceguard failover package services or applications can use EVFS volumes or file systems
mounted on EVFS volumes. You can modify a Serviceguard package control script (for a
legacy package), or a Serviceguard package configuration file (for a modular package) to
enable EVFS volumes and mount file systems on EVFS volumes when a package starts.
• A cluster lock disk can co-exist on an LVM or VxVM volume group with volumes used by
EVFS.
Requirements
To use EVFS with Serviceguard, the system must meet the following conditions:
• HP Serviceguard version A.11.16, A.11.17 or A.11.18 is installed.
• The EVFS volumes used by the package must be built on cluster aware LVM volume groups
or VxVM disk groups.
EVFS and Serviceguard Overview 153