You enable z/OS® systems to use the tape library by defining system names in the Initial Online Status attribute. These system names must also reside in the base configuration of your active SMS configuration. A tape library that is defined to z/OS and physically connected to a system can be online or offline. If a tape library is offline, you can use the VARY SMS,LIBRARY command to bring the tape library online. If you do not set a status, SMS assumes that the tape library is not connected. Ensure that the tape configuration database is available to every system that uses the tape library.