IBM System Storage TS3310, Информация по обслуживанию, Страница: 110 / 531

T011: Drive Over Eject Condition
Description GUI Description: A drive over-ejected a tape cartridge into
the robot's motion path.
Explanation: The library is about to perform a get from a
tape drive and checks the tape drive status to determine if
the tape cartridge is ejected. LTO tape drives have
demonstrated a specific failure mode where they eject a
tape in an abnormal manner. Normally upon eject, the tape
is in a particular position where it is clear of the robot
motion path and it cannot be reloaded due to mechanical
interlock within the tape drive load mechanism. The
historical failure mode is that the tape slips an additional
amount out of the tape drive throat which re-arms the load
mechanism of the tape drive.
Two subsequent problems can occur. The over ejected tape
can become an obstruction hazard for robot moves. In
addition, the robot get operations can then re-trigger the
tape drive load mechanism by bumping the tape during a
get. There can be a “tug of war” between robot and tape
drive or the tape drive can win the tug of war resulting in
the loading of a phantom tape. When the tape drive loads a
phantom tape, there are resulting tape drive errors. The
goal of reporting this problem is to identify tape drives that
over eject tapes to avoid the two types of problems.
Detection Scenarios Library checks drive status prior to moving to perform a
GET. If is trying to determine if the drive is in an unloaded
state and if a cartridge is present. If a cartridge is not
reported as present, the library can assume it was "over
ejected".
Root Causes The drive eject process did not result in the proper
positioning of the ejected cartridge.
Possible CRU Replacements Drive Sled
Resolution Perform the following:
1. “Removing a Drive Sled” on page 8-43.
2. “Replacing a Drive Sled” on page 8-44.
T012: Drive Unload Control Prevented
Description GUI Description: A host issued a SCSI Prevent/Allow Media Removal
command which is preventing the drive from unloading a tape cartridge.
Explanation: The library needs to issue a command to the drive (such as
unload) but cannot perform the operation, because the host issued a
Prevent/Allow Medium Removal SCSI command, preventing media removal.
Detection Scenarios
1. Library tries to issue an unload command.
2. Library tries to issue a command associated with drive unload.
Root Causes A host is either properly or improperly reserving the drive while a user or
host is trying to properly or improperly perform some action on the drive.
Possible FRU Replacements No library FRU is involved. Rather this is an indication that a host may have
orphaned a reserve on the drive.
Resolution Perform “DR016: Resolve Prevent/Allow Media Removal” on page 6-67.
6-8
TS3310 Tape Library Maintenance Information