IWMSRSRG – Register a Server for Sysplex Routing

The purpose of the IWMSRSRG service is to register a server that wishes to participate in sysplex workload balancing. The service allows the caller to identify an address space to be associated with a triplet, corresponding to location name, network id and LU name. This triplet is expected to be unique across all registered spaces in the sysplex, and, should be unique across all networks. The caller can additionally associate the triplet with a host name. Specifying a host name is optional, and if it is not coded it is set to blanks by the system. A list of eligible servers is made available to IWMSRSRS. These work requests include enclaves owned by the space as well as the address space's activity itself.

If this macro is issued to register a LOCATION.NETWORK_ID.LUNAME that already exists on the issuing MVS™ image, the second registration will be ignored (IWMSRDRS should first be used to deregister the triplet). This condition will be identified through a unique return and reason code. Due to timing considerations, sysplex-wide uniqueness is not enforced, and so is the responsibility of the caller.

The caller can additionally associate the server with a health indicator. This is a value between 0 and 100, that indicates the percentage up to which the server is capable of performing its normal work. This health indicator is used by the routing service to modify the routing recommendations according to this indicator. It can be modified by calling this service again with another HEALTH value. In this case the return and reason code for already registered servers will not be returned.

After a server registers by issuing this macro, the sysplex routing service IWMSRSRS can be issued to return a weighted list of registered servers in the sysplex to which work could be directed. Alternatively, IWMSRSRS can be used to obtain a complete list of servers associated with a given location or to obtain the user data associated with each server. Since the propagation of the registration to other systems is asynchronous, a newly registered triplet will not be immediately visible to other systems.

A server is automatically deregistered during job termination or memory termination.