Designing Disaster Tolerant High Availability Clusters, 10th Edition, March 2003 (B7660-90013)

Building a Metropolitan Cluster Using MetroCluster/CA
Configuring Packages for Automatic Disaster Recovery
Chapter 3 107
Configuring Packages for Automatic Disaster
Recovery
When you have completed the following steps, packages will be able to
automatically fail over to an alternate node in another data center and
still have access to the data that they need in order to operate.
This procedure must be repeated on all the cluster nodes for each
MC/ServiceGuard package so the application can fail over to any of the
nodes in the cluster. Customizations include editing an environment file
to set environment variables, and customizing the package control script
to include customer-defined run and halt commands, as appropriate. The
package control script must also be customized for the particular
application software that it will control. Consult Managing
MC/ServiceGuard for more detailed instructions on how to start, halt,
and move packages and their services between nodes in a cluster. For
ease of troubleshooting, you can configure and test one package at a
time.
1. Create a directory /etc/cmcluster/pkgname for each package:
# mkdir /etc/cmcluster/pkgname
2. Create a package configuration file with the commands:
# cd /etc/cmcluster/pkgname
# cmmakepkg -p pkgname.config
Customize the package configuration file as appropriate to your
application. Be sure to include the pathname of the control script
(/etc/cmcluster/pkgname/pkgname.cntl) for the RUN_SCRIPT and
HALT_SCRIPT parameters.
3. In the <pkgname>.config file, list the node names in the order in
which you want the package to fail over. It is recommended for
performance reasons, that you have the package fail over locally
first, then to the remote data center.
Set the value of RUN_SCRIPT_TIMEOUT in the package configuration
file to NO_TIMEOUT or to a large enough value to take into
consideration the extra startup time required to obtain status from
the XP Series disk array.