Designing Disaster Tolerant High Availability Clusters, 10th Edition, March 2003 (B7660-90013)
Building a Metropolitan Cluster Using MetroCluster/CA
Preparing an MC/ServiceGuard Cluster for MetroCluster /CA
Chapter 396
8. Determine which devices will be used by the application package.
Define a device group that contains all of these devices. The device
group name (dev_group) is user-defined and must be the same on
each host in the MetroCluster that accesses the XP Series disk array.
It is recommended that you use a name that is easily associated with
the package. For example, a device group name of “db-payroll” is
easily associated with the database for the payroll application. A
device group name of “group1” would be more difficult to easily relate
to an application. The device group name MUST be unique within
the cluster.
The device name (dev_name) is also user-defined and must be the
same on each host in the MetroCluster that accesses the XP Series
disk array. The device name (dev_name) must be unique among all
devices in the cluster. However, the TargetID and LU# fields for each
device name may be different on different hosts in the cluster, to
allow for different hardware I/O paths on different hosts.
9. Edit the following sections of the Raid Manager configuration file
that was created in a previous step:
HORCM_DEV Include the devices and device group used by the
application package. Only one device group may be
specified for all of the devices that belong to a
single application package.
HORCM_INST Supply the names of only those hosts that are
attached to the XP Series disk array that is remote
from the disk array directly attached to this host.
For example, with a MetroCluster of 6 nodes, 2 of
which are Arbitrators, you would specify only hosts
3 and 4 in the HORCM_INST section. Host 1 would
have previously been specified in the HORCM_MON
section.
See the file horcm0.conf.<sys-name> in
/opt/cmcluster/toolkit/SGCA/Samples/ for an
example.
10. Restart the Raid Manager instance so that the new information in
the configuration file is read. Use the following commands:
# horcmshutdown.sh <instance-#>
# horcmstart.sh <instance-#>