Escon Host Attachment - IBM TotalStorage 3494 Tape Library Operator's Manual

v Logical library partitioning
v Operator interface
v Logical volume inventory
Logical Library Partitioning
To support the product requirement that a VTS can coexist with current 3490 tape
drives and native 3590 or 3592 tape drives in the same 3494 Tape Library, the
Library Manager partitions the physical library into logical libraries. This must be
done because a VTS presents the image of 3490E-type tape drives and yet cannot
read or write a real 3490 cartridge. By placing a VTS in its own logical library, host
software is not able to attempt to allocate a VTS drive for a real 3490 mount and
vice versa.
A logical library can contain either of the following subsystems:
v A single VTS or TS7700 Virtualization Engine
v Current 3490 tape drives or native 3590 or 3592 tape drives
Each logical library has its own unique library sequence number and appears as a
separate physical library to the hosts attached to the subsystems in that partition.
Note: Currently, up to two VTSs (only one of which may be a 3494 B16 VTS) are
allowed in a physical library.
Operator Interface
The Library Manager console is used to perform the setup, management, and
status functions needed to support a VTS.
Logical Volume Inventory
The database in the Library Manager is expanded to handle the large number of
logical volumes that a VTS uses. There are also new operator functions that allow
the addition of logical volumes by specifying a volume serial number range
through the Library Manager console (see Figure 176 on page 281).

ESCON Host Attachment

The ESCON Host Attachment provides attachment for 3494 B18, B10, and B20
VTSs.
The 3494 B18 VTS can be configured with one of the following:
v two standard ESCON host channel attachments
v two or four enhanced ESCON host channel attachments (FC 3302 withdrawn)
v two or four Extended Performance ESCON Channel attachments (FC 3412)
v two enhanced ESCON host channel attachments and two Extended Performance
ESCON Channel attachments
When the Performance Accelerator (FC 5236) is installed, the Extended
Performance ESCON Channel attachments can be activated for four or eight
ESCON channel attachments when the FC 4010, Peer-to-Peer Copy Base, is not
installed. This can be done by ordering FC 3418, Activate Additional ESCON
Channels. Each ESCON attachment supports 64 logical paths. With four adapters,
including FC 3418s, 512 logical paths can be configured to a single 3494 B18 VTS.
The 3494 B10 VTS can be configured with up to four Extended Performance
ESCON Channel attachments. Each ESCON attachment supports 64 logical paths.
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Chapter 3. Operational Characteristics