Database Reference
In-Depth Information
The standby database can be added by using the same procedure as described in the level 2 high-availability
section of this chapter. Using Enterprise Manager Cloud Control, it is not possible to create a RAC standby. However,
using deployment procedures, a single-instance standby database can be converted to a RAC standby database.
Level 4—MAA with Standby Site
The previously described high-availability levels would provide protection for unplanned and planned downtime.
Using an SLB with multiple Oracle Management Services will provide service in the event of a single OMS becoming
unavailable. Using Real Application Clusters coupled with a local Data Guard provides the highest levels of availability
for the repository with no downtime if a host is unavailable. If a failover or switchover operation is performed,
minimal downtime will occur. However, if a complete site failure arises at the primary location, the entire Enterprise
Manager Cloud Control environment will become unavailable, leading to potential disruptions in service for other
applications that rely on the infrastructure.
Prerequisites
Configuring a standby Enterprise Manager Cloud Control system at a separate site provides high availability and
protects against site failures. This configuration includes multiple active/active OMS servers behind a SLB in addition
to a RAC primary and standby database in a Data Guard at both the primary site and another off-site location.
Prerequisites for standby management services are as follows:
•
Configure the primary site by using MAA configuration, as described previously.
•
Configure the standby site by using similar hardware and resources to ensure that no loss of
performance occurs after switching to the standby site.
•
Shared storage used for the Software Library should be replicated to the standby site. The path
for the Software Library should also be identical at both locations. Consider using disk-based
replication or software-based replication such as rsync
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or something similar.
•
A second SLB should also be deployed at the standby site to ensure complete redundancy in a
disaster recovery environment. Use vendor solutions that provide VIP failover from primary to
standby sites.
After these prerequisites have been met, install and configure the standby management services by using
instructions in the
Oracle Enterprise Manager Cloud Control 12c Administrator's Guide
.
Standby Management Server Installation
To install a standby management server, you perform a software-only installation by using either a modified version
of the Add Management Service deployment procedures from the Procedure Library or Oracle Universal Installer. The
next example walks you through the steps used in the former method.
If a firewall exists between the primary and standby sites, it should be configured to allow communication for the
HTTP Console, HTTPS Console, HTTP Agent Upload, and HTTPS Agent Upload ports as well as the Admin Server and
Node Manager ports.
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rsync is software that enables replication of files and directories from one system to another while minimizing data transfer
through the use of deltas.
