Magnetic Tape Cartridge Devices - Fujitsu Siemens Computers SX series User Manual

Magnetic tape cartridge devices

9.4 Magnetic tape cartridge devices
Multiple systems can be granted access to the same magnetic tape cartridge device in a
"Storage Area Network" (SAN). Such an environment requires the connected systems to be
synchronized. If they are not coordinated it is not possible to operate the MTC device
properly even if you ensure that only one application ever uses the device at a time because
tests are performed periodically by the systems which can result in the position of the tape
being changed and thus to read or write errors in the application.
X2000 coordinates operation of the MTC device in a homogeneous network of X2000-
based BS2000 systems in which the MTC device is configured as described below.
While this configuration has not been completed for all connected systems no MTC device
may be used on an X2000-based BS2000 system.
Nor may an MTC device be used on an X2000-based BS2000 system if a system of a
different type (BS2000 S server, Solaris, Linux, etc.) can access the device.
In X2000 MTC devices have the configuration type NTTAPEO, NTTAPEA, MKTAPEO or
MKTAPEA. X2000 supports alternate exclusive use of a correctly configured MTC device by
multiple X2000-based BS2000 systems.
The exclusive use of an MTC device by a BS2000 system is started by issuing the
command ATTACH-DEVICE for the device or by assigning the device in SLED.
An MTC device becomes free for exclusive use at another BS2000 system when it is
released with the command DETACH-DEVICE or by SLED.
Any attempt to occupy an MTC device that is being used by another BS2000 system will be
rejected (with the message text ASSIGNED ELSEWHERE).
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Global X2000 functions
U41272-J-Z385-3-76