LPAR Hosting

A logical partition (LPAR) is a part of the firmware of IBM System Z Mainframes, virtualized as a separate computer. In effect, a physical machine is often partitioned into multiple logical partitions, each hosting a separate instance of an OS.

Each LPAR functions independently and can run any mainframe operating system. Alternatively, installation planners can elect to share I/O devices across several LPARs.  Hence, the operating systems in each LPAR can be separate and have their own operator console. This ensures there is no effect on the other LPARs if a system in one LPAR crashes.

One or more system processors can be assigned by the system admin for the exclusive use of an LPAR. Also, the administrator can allow all processors to be used on some or all LPARs. The firmware provides a dispatcher to share the processors among the selected LPARs. The administrator can decide the number of concurrent processors executing in each LPAR. Also, the administrator can provide weightings for various LPARs; for instance, specifying that LPAR1 should receive twice the maximum amount of processor time as LPAR2.

We can say there is no difference between, for example, three separate mainframes running z/OS (and sharing most of their I/O configuration) and three LPARs on the same mainframe doing the same thing. With minor exceptions, z/OS, the operators, and applications cannot detect the difference.

Maintec Technologies offers the most flexible, reliable, and cost-effective LPAR hosting services to meet the client’s specific needs.