IBM System Storage TS3500, Introduction And Planning Manual

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v
If you convert an existing HD frame from a service bay to an expansion frame, a
Capacity on Demand feature (1645 or 1646) is required in order to use the full
capacity of the frame. If an HD frame is ordered to be used as service bay B, it
does not require a Capacity on Demand feature.
v
In order to support mixed media in an HD library with dual accessors, service
bay B must be a model Dxx frame. This configuration requires feature code 1697,
which ensures that the service bays provide both LTO and 3592 HD test slots.
v Expansion frame Model D32 cannot be used as service bay B.
For information about library availability and performance, see “Library
performance” on page 83.
High density technology
The TS3500 Tape Library offers high-density, storage-only frame models (HD
frames) designed to greatly increase storage capacity without increasing frame size
or required floor space. The new HD frames (Model S24 for 3592 tape cartridges
and Model S54 for LTO Ultrium tape cartridges) contain HD storage slots.
HD slots contain tape cartridges in a tiered architecture. The cartridge immediately
accessible in the HD slot is a Tier 1 cartridge. Behind that is Tier 2 and so on. The
maximum tier in an LTO Ultirum (Model S54) HD slot is Tier 5. The maximum tier
in a 3592 (Model S24) HD slot is Tier 4 because the 3592 tape cartridge is slightly
longer than the LTO Ultrium cartridge. The single-deep slots on the door side of
HD frames are referred to as Tier 0 slots. On the left, Figure 6 on page 10 shows
the inside of an HD frame from the side. On the right, Figure 6 on page 10 shows a
top-down view of one row of an HD frame with cartridges in Tiers 0 (door side),
1, 2, and 3.
Chapter 1. Introduction
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