Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access EVA A.05.01

1. Ensures that the database is completely shut down at the formerly active sub-cluster.
2. Fails over the disk device group to the newly active sub-cluster so that the database replica
LUNs become available for read-write access.
3. Starts the CVM disk groups and CFS mount points for the database at the newly active
sub-cluster, and then starts the RAC database there.
While these steps are being performed, client connections cannot be made to the database. Also,
there is no FAN event delivered to indicate site failover, so existing client connections may be
susceptible to delays as long as the TCP keep alive timeout in some cases, before a reconnect is
attempted.
To automatically reconnect clients to the database on a site failover, the Oracle Net service names
must include VIPs configured at both sub-clusters. For example:
hr_serv1 =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = SFO_1v.hp.com)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = SFO_2v.hp.com)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = SJC_1v.hp.com)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = SJC_2v.hp.com)(PORT = 1521))
(LOAD_BALANCE = yes)
)
(CONNECT_DATA=
(SERVICE_NAME=hr_serv1)
)
)
Configuring SGeRAC cluster interconnect subnet monitoring
SGeRAC provides a feature to monitor the Oracle Clusterware interconnect subnet and to ensure
that at least one RAC instance survives when a failure takes down the entire interconnect subnet
in the cluster.
To configure this feature, the interconnect subnet must be specified in a separate MNP package
using the CLUSTER_INTERCONNECT_SUBNET package attribute. The Clusterware MNP package
for the Clusterware sub-cluster must have a dependency specified on this interconnect MNP package.
For more information on network planning for Oracle Clusterware communication, see the latest
edition of Using Serviceguard Extension for RAC manual available at http://www.hp.com/go/
hpux-serviceguard-docs-> HP Serviceguard Extension for RAC.
The Oracle Clusterware interconnect subnet for a site Clusterware sub-cluster is a subnet spanning
only the nodes in that site (it is not required to route it across the sites). The interconnect subnets
at each site is packaged in a separate MNP package.
To configure the SGeRAC Cluster Interconnect packages:
1. Create a package directory on all nodes in the site.
# mkdir -p /etc/cmcluster/pkg/sfo_ic
2. Create a package configuration file and control script file. Use site-specific names for the files.
You must follow the legacy package creation steps.
# cmmakepkg -p sfo_ic.conf
# cmmakepkg -s sfo_ic.cntl
3. Specify a site-specific package name in the package configuration file.
4. Specify only the nodes in the site for the node_name parameter.
5. Specify the package type as MULTI_NODE.
6. Specify the SGeRAC Cluster Interconnect as CLUSTER_INTERCONNECT_SUBNET.
7. Save and apply the package configuration file.
# cmapplyconf –P sfo_ic.conf
118 Configuring Oracle RAC in SADTA