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Defining High Availability Policies

This task is a step in Process of Infrastructure Planning.

This infrastructure planning task defines business policies regarding availability of servers.

See also High Availability Deployment Planning.

Siebel Servers

For each business location, assess the impact of losing each server component. Consider the possibility of the component failing, rather than the hosting platform itself. Individual server components that are important to normal application function must be identified in your planning and review phases. Work closely with your implementation team to identify all of the components that could represent single points of failure.

After you complete this analysis, define high availability policies for all of the applications and services. Decide how long your business can tolerate not having access to key applications. Also, decide how long your business can tolerate degraded performance.

For example, a company decides that Siebel Call Center must run 24 hours a day, seven days a week, and that the maximum acceptable downtime is 30 minutes. The company also decides that the maximum time it can accept degraded performance is one hour.

Finally, at each business location, list all of the server components to which each policy applies. This analysis forms the basis for implementing a high availability strategy as part of hardware planning.

Database Platform and Data Integrity

The server platform that hosts the Siebel database is crucial to Siebel CRM deployment operations. For this reason, it is important to define high availability and data integrity policies specifically for the database server. The following policies are recommended:

• Cluster database servers to protect against platform hardware failures.
• Use redundant disk arrays (RAIDs) for disk storage. RAID 1+0 is recommended because it provides maximum performance, and there is no data loss if a disk fails. Do not implement RAID 0 arrays. RAID 0 offers good performance but does not protect data adequately in the event of a disk failure.
• Enable transaction logging.
• Observe the following recommendations for storing database files:
  • Store data and indexes on separate disk subsystems.
  • Store active log files and archived log files on separate disk subsystems.
  • Store the database and database control files on separate disk subsystems.
• To allow for good OLTP performance, set up four rollback segments (if you choose to use them) for each 20 to 40 users. For Initial extents or Next extents, set up rollback extents sized to 100 KB. If you use Siebel EIM, then also create several additional, large rollback segments to support Siebel EIM loads.

Siebel Gateway

The Siebel Gateway maintains the Siebel Gateway registry to store the configuration information for all of the Siebel Servers in all of the Siebel Enterprise Servers managed by the Siebel Gateway. Loss of the Siebel Gateway due to a disk failure could bring your Siebel CRM deployment to a halt while you restore the Siebel Gateway, unless you take measures to provide high availability for the Siebel Gateway.

As of Siebel CRM 18.5 Update, Siebel CRM supports an optional native clustering feature for Siebel Gateway to provide high availability benefits to Siebel CRM customers. This feature works at the software level and is the preferred and recommended approach for clustering the Siebel Gateway. To use this feature, you install Siebel Gateway on multiple nodes and configure clustering using Siebel Management Console. Clustering is supported for both the Siebel Gateway service (application container) and the Siebel Gateway registry (Apache ZooKeeper). If an individual node goes down within the Siebel Gateway cluster, then the Siebel Application Interface or Siebel Server client connection switches to another available node. After any Siebel Gateway cluster node goes down, when it is restarted, the node will again participate in the cluster. For more information, see the Siebel Installation Guide for the operating system you are using.

Optionally, you can install a RAID or some other type of redundant disk configuration on your Siebel Gateway.

Siebel Mobile Web Client Users

A Siebel Server temporarily stores transaction files that move to and from users of the Siebel Remote client, generally called Siebel Mobile Web Clients. The loss of these files results in the need to re-extract the database for all of the affected mobile users. (Siebel Remote supports synchronization of data between Siebel Mobile Web Clients and the Siebel database, over an Internet connection.)

It is strongly recommended that you install a RAID or some other type of redundant disk configuration on Siebel Servers that run Siebel Remote.