Partitioned servers

Using Domino® server partitioning, you can run multiple instances of the Domino® server on a single computer. By doing so, you reduce hardware expenses and minimize the number of computers to administer because, instead of purchasing multiple small computers to run Domino® servers that might not take advantage of the resources available to them, you can purchase a single, more powerful computer and run multiple instances of the Domino® server on that single machine.

On a Domino® partitioned server, all partitions share the same Domino® program directory, and thus share one set of Domino® executable files. However, each partition has its own Domino® data directory and NOTES.INI file; thus each has its own copy of the Domino® Directory and other administrative databases.

If one partition shuts down, the others continue to run. If a partition encounters a fatal error, Domino's fault recovery feature restarts only that partition, not the entire computer.

Partitioned servers can provide the scalability you need while also providing security. As your system grows, you can migrate users from a partition to a separate server. A partitioned server can also be a member of a cluster if you require high availability of databases. Security for a partitioned server is the same as for a single server.

When you set up a partitioned server, you must run the same version of Domino® on each partition. However, if the server runs on UNIX, there is an alternative means to run multiple instances of Domino® on the server: on UNIX, you can run different versions of Domino® on a single computer, each version with its own program directory. You can even run multiple instances of each version by installing it as a Domino® partitioned server.

If the server runs onIBM® i, you can use multi-versioning support to install and run multiple Domino® servers at different release levels.

Deciding whether to use partitioned servers

Whether or not to use partitioned servers depends, in part, on how you set up Domino® domains. A partitioned server is most useful when the partitions are in different Domino® domains. For example, using a partitioned server, you can dedicate different Domino® domains to different customers or set up multiple Web sites. A partitioned server with partitions all in the same Domino® domain often uses more computer resources and disk space than a single server that runs multiple services.

When making the decision to use partitioned servers, remember that it is easier to administer a single server than it is to administer multiple partitions. However, if your goal is to isolate certain server functions on the network -- for example, to isolate the messaging hub from the replication hub or isolate work groups for resource and activity logging -- you might be willing to take on the additional administrative work. In addition, running a partitioned server on a multiprocessor computer may improve performance, even when the partitions are in the same domain, because the computer simultaneously runs certain processes.

To give HCL Notes® users access to a Domino® server where they can create and run Domino® applications, use a partitioned server. However, to provide customers with Internet access to a specific set of Domino® applications, set up an xSP server environment.

Note: xSP is not supported on system IBM® i.

Deciding how many partitions to have

The number of partitions you can install without noticeably diminishing performance depends on the power of the computer and the operating system the computer uses. For optimal performance, partition multiprocessor computers that have at least one, and preferably two, processors for each partition that you install on the computer.