F Metrocluster Command Reference for Preview Utility

This appendix describes the Data Replication Storage Failover Preview utility. This appendix discusses the following topics:

•Overview of Data Replication Storage Failover Preview

•Command Reference

•Sample Output of the cmdrprev Command

Overview of Data Replication Storage Failover Preview

In an actual failure, packages are failed over to the standby site. As part of the package startup, the underlying storage is failed over based on the parameters defined in Metrocluster environment file. The storage failover can fail due to many reasons and can be categorized as the following:

•Incorrect configuration or setup of Metrocluster and data replication environment

The storage failover can fail if the Metrocluster Environment file contains syntax errors, or invalid parameter values, or the installed Metrocluster binaries are corrupt or have incorrect file permissions.

Also in the case of Continuous Access EVA, the SMI-S service on the WMS could be down or the mccaeva.conf file is corrupt or stale. In the case of Continuous Access P9000 or XP, the possible configuration errors are invalid horcm file, or the command device is not functional.

•Invalid data replication state

The data may not be in the write-order, which can be due to a track copy at the time of the failover attempt. Also, the data is not current (lagging behind the primary) and the Metrocluster environment variables are not set correctly to allow a failover on non-current data.

The command cmdrprev previews the failover of data replication storage. It determines if storage failover would be successful in an actual package failover scenario. This command can be used in both Metrocluster and Continentalcluster installations. If the preview fails, the cmdrprev command displays on stdout a detailed log that identifies the cause for failure.

NOTE: Detailed messages from the preview process are logged into the stdout.

The command exit value indicates if the storage failover in an actual package will succeed or not. Table 41 describes the exit values of the command.

Table 41 Command Exit Value and its Description

Value

Description

 

 

-1

The data replication storage failover preview failed. This indicates that in the event of an

 

actual recovery process, the data replication storage failover will not succeed from on any

 

node in the cluster.

 

The data replication storage failover preview command failed, due to invalid command usage

 

or due to invalid input parameters.

 

 

0

The data replication storage failover preview is successful from a specific node.

 

This indicates if data replication storage failover will be successful in the event of a package

 

failover.

 

 

1

The data replication storage failover preview failed.

 

This indicates that in the event of an actual recovery process, the data replication storage

 

failover will not succeed from on any node in the cluster.

 

 

2

The data replication storage failover preview failed due to node specific error conditions or

 

due to transient conditions.

 

 

Overview of Data Replication Storage Failover Preview 503