Assigning a UID of 0
Although sometimes appropriate, the least desirable method of defining superusers is to assign a UID of 0 in the UID parameter in the OMVS segment of the ADDUSER or ALTUSER commands. In this environment, you risk entering commands that can damage the file system.
User ID SMORG UID(0) - used for system maintenance User ID SMORG1 UID(7) - used for regular programming
ALTUSER SMORG OMVS(UID(0) HOME('/') PROGRAM('/bin/sh')) ALTGROUP SYS1 OMVS(GID(0))
You might choose to assign UID(0) to multiple RACF user IDs. However, try to minimize the use of UID(0). Assignment of UID(0) should be limited to the user associated with started procedures such as the OMVS kernel and the user who installs the ServerPac. It should be avoided for the user IDs belonging to the real users whenever possible.
ALTUSER SMORG OMVS(UID(0) SHARED HOME('/') PROGRAM('/bin/sh'))