IBM Tape Library Magstar 3494 - Manual (Page 36)

Figure 12 on page 15 shows the following functional components of the Model HA1
Left Service Bay from the right front:
1
Cartridge storage cells
Are located on the interior side of the front doors on the 3494 and on the
back interior wall but are for service use only.
2
Barrier door
Used by service personnel to separate the service bay from the main aisle
of the 3494. This allows for concurrent service of the accessor and the
associated hardware.
Figure 11. Model B18 Virtual Tape Server Functional Components (rear)
14 Magstar 3494 Tape Library Operator Guide