Oracle StorageTek SL3000, Руководство пользователя

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Library Modules
1-4 StorageTek SL3000 Library Guide
Figure 1–3 DEM Rear View
Figure Legend:
1.
Tape drives
2.
Drive DC power supplies
3.
Ethernet switches (optional)
4.
Power distribution unit
Cartridge Expansion Module (CEM)
The CEM provides additional cartridge storage. There are no tape drives present
within this module. CEMs on the end of the library can be converted to PEMs (see
"Parking Expansion Module (PEM)" on page 1-5). A maximum of eight CEMs are
supported in a single library. The initial CEM should be installed to the right of a Base
module, then a second to the left of the DEM/Base module, a third to the right, and
the fourth one to the left, and so on. This alternating method maximizes library
performance.
CEM Configuration Options
■
438 to 620 cartridge capacity (see "Calculating Physical Capacity" on page 1-17).
■
CAP (optional). See "Rotational Cartridge Access Port (CAP)" on page 1-7.
■
Placement to the left or right of a Base module and DEM
■
A maximum of four CEMs on each side of centerline (eight total)
Access Expansion Module (AEM)
An AEM has a large cartridge access door used for bulk loading and unloading of up
to 234 cartridges. Additionally, a library with two AEMs supports the redundant