Designing Disaster Recovery Clusters using Metroclusters and Continentalclusters, Reprinted October 2011 (5900-1881)

then they need to be explicitly specified while creating the Metrocluster Continuous Access
modular package configuration file.
The following example shows the package IP, the filesystem, and the monitor subnet module
included along with the Metrocluster Continuous Access EVA module.
# cmmakepkg –m dts/mccaeva –m sg/filesystem –m sg/monitor_subnet
-m\ sg/package_ip temp.config
NOTE: Metrocluster is usually used with applications such as Oracle. So, the application
toolkit module must also be included when Metrocluster is used in conjunction with an
application.
For example:
When Metrocluster is used in conjunction with the Oracle toolkit, the Oracle toolkit module
and other required modules must also be included with the Metrocluster Continuous Access
EVA module. So, following is the command that needs to be used:
# cmmakepkg –m dts/mccaeva –m sg/filesystem -m sg/package_ip -m\
ecmt/oracle/oracle temp.config
2. Create a directory for storing the Metrocluster Continuous Access EVA environment file on all
the nodes where the package is designated to run.
# mkdir /etc/cmcluster/pkgname
3. Provide the right permissions for the directory on all the nodes.
# chmod 755 /etc/cmcluster/pkgname
4. In the newly created modular package configuration file, temp.config, specify the following:
a. The directory created previously for the dts/dts/dts_pkg_dir attribute.
b. The node names in the order in which the package needs to failover.
To avoid an impact on performance, it is recommended to have the package first failover
to local nodes followed by failing over to the remote data center.
For the failover_policy parameter, Metrocluster failover packages can be configured
to use any of the Serviceguard defined failover policies. The site_preferred and
site_preferred_manual failover policies are introduced in Serviceguard specifically
for Metrocluster configurations. The site_preferred value implies that when a
Metrocluster package has to fail over, it will necessarily failover to a node within the
same site of the node it last ran on. Only when there is no other configured node available
within the same site, the package fails over to a node at the other site. The
site_preferred_manual failover policy provides automatic failover of packages
within a site and manual failover across sites. To use either of these policies the underlying
cluster must be configured with sites and each cluster nodes should be associated to a
site. For information on configuring the failover policy to site_preferred or
site_preferred_manual, see “Site Aware Failover Configuration” (page 26).
c. The value of run_script_timeout attribute in the package configuration file. Set this attribute
to NO_TIMEOUT or to a large enough value to take into consideration the extra startup
time required to obtain status from the EVA disk array.
d. The package_type attribute. It must always be specified as Failover.
e. The volume group attribute. Specify the required logical volume group name to the
volume group attribute.
f. If other Serviceguard modules are included, then specify values for the included module
attributes accordingly.
g. If any application module is included, then list values for the included module attributes
accordingly.
Building a Metrocluster Solution with Continuous Access EVA 235