Restrictions on RLS Mode Usage

There are several restrictions on using RLS mode:

Master catalogs are currently not supported in RLS mode. Ensure that any catalog in RLS mode is not being shared as a master catalog by any system in the plex.
RLS protocol cannot be used simultaneously with either ECS or VVDS protocol for a catalog. This is enforced by the SMSVSAM address space. If you attempt to use a catalog currently in RLS mode from a non-RLS system in the sysplex, the associated catalog request will fail with return code RC4 and reason code RSN124. If a catalog is currently in either ECS mode or VVDS mode and is shared by a system that cannot support RLS for catalogs, the attempt to use the catalog in RLS mode will also fail with return code RC4 and reason code RSN124.
Note: If you attempt to use a catalog that is currently RLS-active from a system outside the sysplex, the request might break the catalog.
No more than 1024 catalogs can currently be opened from any single system using RLS.
All systems sharing the catalog in RLS mode must be on the release that supports RLS for catalogs and have the SMSVSAM address space available.