Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access XP P9000 for Linux B.01.00.00

perspective, there is no difference between a pair created from internal devices and a pair
created using external devices.
See the HP StorageWorks XP or P9000 documentation for information about the configuration
requirements of external storage devices attached to XP or P9000 arrays and supported
external storage devices.
9. Determine the devices used by the application package. Define a device group that contains
all of these devices. 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” is more difficult to
relate to an application.
Edit the Raid Manager configuration file (horcm0.conf) to include the devices and device
group used by the application package. Only one device group might be specified for all of
the devices that belong to a single application package. These devices are specified in the
field HORCM_DEV or HORCM_LDEV.
Also complete the HORCM_INST field, by supplying the names of only those hosts that are
attached to the XP or P9000 disk array that is remote from the disk array that is directly
attached to this host.
For Example, if node 1 and node 2 are in the source disk site and nodes 3 and node 4 are
in the recovery site, you must specify only nodes 3 and node 4 in the HORCM_INST field in
a file you are creating on node 1 on the source disk site. Node 1 must have previously been
specified in the HORCM_MON field.
10. Restart the Raid Manager instance so that the new information in the configuration file is read.
# horcmshutdown.sh <instance-#>
# horcmstart.sh <instance-#>
11. Repeat these steps on every host that will run this particular application package. If a host
might run more than one application package, you must incorporate device group and host
information for each of these packages.
NOTE: The Raid Manager configuration file must be different for every host, especially for
the HORC_MON and HORC_INST fields.
12. If not previously done, create the paired volumes:
# paircreate -g <devgroup> -f <fencelevel> -vl -c 15
This command must be issued before creating volume groups or disk groups. For creating a
pair of journal groups, see the section, “Pair creation of Journal Groups” (page 18)
CAUTION: Paired devices must be of compatible sizes and types.
When using the paircreate command to create PVOL/SVOL Continuous Access pairs,
specify the -c 15 switch to ensure the fastest data copy from PVOL to SVOL.
Pair creation of Journal Groups
The Continuous Access Journal has the same characteristic as Continuous Access Asynchronous
such that Raid Manager controls Continuous Access Journal similar to Continuous Access
Asynchronous.
The Raid Manager configuration of the device group pair for Continuous Access Journal is exactly
the same as the configuration of the Continuous Access Asynchronous device group pair. In the
/etc/horcm0.conf file, do not specify any journal volumes or journal group number. Only
data volumes (device group and its devices) must be in the configuration file.
18 Configuring an application in a Metrocluster environment