Enabling a Catalog in RLS Mode

Only SMS-managed catalogs residing on SMS-managed volumes can be used for RLS. To make a catalog RLS-eligible, a LOG parameter is available on the IDCAMS DEFINE and ALTER commands. Specify LOG(NONE) to make a catalog eligible for using the RLS protocol, as opposed to the VVDS or the ECS protocol. However, the system will not actually use the RLS protocol unless:

RLSENABLE attribute is specified AND
The STORCLAS and its cache set information are specified AND
The SMSVSAM address space is active on the system AND
The catalog is not currently open in either VVDS mode or ECS mode from any system in release 1.13 of z/OS® or below.

You can alter the LOG parameter of a catalog at any time. If you nullify the parameter or specify RLSQUIESCE and the catalog is currently using RLS mode, it will be converted back to either VVDS or ECS mode on all systems that are sharing it. This is convenient if you find that the catalog must be accessed by a system that does not support the RLS protocol.