HP StorageWorks EVA Cluster Extension Software Administrator Guide (T3667-96045, April 2010)

User configuration file
EVA Cluster Extension provides a user configuration file to customize failover behavior. You can
specify all customizable objects of EVA Cluster Extension in this file.
See “User configuration file” on page 73 for more information.
Resource configuration file (Linux only)
The EVA Cluster Extension resource configuration file is used to configure resources created using
RHCS or SLE HA. The contents of this file are the same as the UCF.cfg file. The APPLICATION name
tag in the file must match the service name property for RHCS and the app name property for SLE
HA.
Force flag
The force flag forces EVA Cluster Extension to skip the internal logic and enables write access to the
local vdisks regardless of the DR group member state. You can set this flag when you are sure that
the current site contains the latest data, even though a previous application service startup process
failed because EVA Cluster Extension discovered a DR group member state that could not be handled
automatically.
To use the force flag feature, before starting the application service that uses EVA Cluster Extension,
you must create a file called application_name.forceflag in the directory specified by the
ApplicationDir property. The application_name is the name of the EVA Cluster Extension resource.
Before creating this file, ensure that the application service is not running elsewhere. This file is removed
after it is detected by EVA Cluster Extension.
You cannot use the force flag if the local vdisk state is a combination of destination and copying,
which indicates that a copy operation is in progress. A disk cannot be put in read/write access mode
when a write operation is in progress to that vdisk; in this case, EVA Cluster Extension returns a global
error.
Planning for EVA Cluster Extension
Consider the dependencies described in this section before configuring EVA Cluster Extension.
HP Command View EVA and HP SMI-S EVA dependencies
EVA Cluster Extension depends on HP Command View EVA and HP SMI-S EVA, as well as the cluster
software it is integrated with.
Before you configure EVA Cluster Extension, verify that the host and storage systems are properly
configured. Ensure that:
• The storage system and its remote peer have been properly configured.
• The host system recognizes the storage systems.
• The Continuous Access EVA links are working properly in both directions.
• You are familiar with the disk configuration of the operating system.
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