Database Reference
In-Depth Information
Level 3
In a
level 3
configuration, the OMS is installed using an active/active configuration, requiring a local load balancer.
The repository database is protected by both Real Application Clusters (RAC) and local Data Guard. This level is
shown in Figure
1-5
.
EM12c
Console
Target with
OMA /plug-in
Target with
OMA/plug-in
Target with
OMA /plug-in
Load balancer
Shared
Storage
Active
OMS
Standby
OMS
OMR with
RAC / local
Data Guard
Figure 1-5.
Schematic diagram of a level 3 deployment
Level 4
Level 4
is the deployment level providing the most scalability and availability. In this case, the OMS is running in
an active/active configuration on a primary site (just like level 3), but additional standby OMS installations are at a
remote site. (Note that because of network latency requirements between the OMS and the repository being less than
1 millisecond consistently, the remote site cannot be running an active OMS). This configuration requires a local load
balancer at both the primary and standby sites. The repository database is again running on RAC, but in this case
the standby RAC database is located at the disaster recovery site. As you can tell, this is quite a complex architecture,
shown in Figure
1-6
(without all the lines of communication that would make it even harder to understand).
