WebSphere system HA level 6
For WebSphere system HA level 6, as shown in Figure 8-8, operations will not stop because of a failure in any component at any site. Geographical clustering is used to synchronize data between two sites. Clients can access both sites at the same time; therefore, scalability and performance are also enhanced. When one data center fails, the other data center will pick up all of the traffic. However, since both sites need to be synchronized in real time, the two sites cannot be far away because of communication latency.
Figure 8-8 WebSphere system HA level 6
In summary, we have many choices regarding HA technologies and/or HA topologies for the end-to-end WebSphere system, as shown in Figure 8-9 for HA technologies and in Figure 8-10 for HA best possible topologies.
Figure 8-9 HA technologies for end-to-end WebSphere system components
Figure 8-10 Two WebSphere administrative domains HA topology
Multiple WebSphere administrative domains (cells) provide not only the capacity for migration and upgrades of WebSphere, application software, and hardware without interruption of WebSphere services (7x24 upgrades/migration), but also make the deployment of different versions of WebSphere possible (WebSphere V4.x and V5.x are not supported in the same domain).
Multiple smaller domains may also provide better performance than a single large domain (cell), because there is less interprocess communication in a smaller domain. However, multiple WebSphere administrative domains add substantially more maintenance effort, since administration must be performed on each domain. Scripts together with a network file system can reduce daily administration efforts for multiple WebSphere administrative domains.
WebSphere is a trademark of the IBM Corporation in the United States, other countries, or both.
IBM is a trademark of the IBM Corporation in the United States, other countries, or both.