Hi Larry,
Thanks for your inputs. The problem happened again over the weekend.
Yup, there is only one tape drive. It seems, I was not running the diags tool properly and was actually testing the library, not the drive. The new test I ran with diags does show an initialization failed on the tape drive.

These are the stats for write errors on it:

The ADAMM.log file content for the past few days:
[3792] 03/25/15 08:37:17.664 PnP Device Paths:
Scsi Address
Prt :Bus :Tar :Lun Device Path
----------------------------------- ---------------------------------------------------------------
00000003:00000000:00000003:00000000 \\?\scsi#sequential&ven_ibm&prod_ult3580-hh4#5&3433385&1&000300#{53f5630b-b6bf-11d0-94f2-00a0c91efb8b}
----------------------------------- ---------------------------------------------------------------
[3792] 03/25/15 08:37:17.664 Read Device Inquiries - start
[3792] 03/25/15 08:37:17.664 Device: \\.\Tape0
[3792] 03/25/15 08:37:18.101 Device: \\.\MediumChanger1
[3792] 03/25/15 08:37:18.397 Device: \\.\Bkup2Dsk
[3792] 03/25/15 08:37:18.678 Read Device Inquiries - end
[3792] 03/25/15 08:37:18.678 Serialize Devices:
[3792] 03/25/15 08:37:18.974 Device Discovery:
[3792] 03/25/15 08:37:18.974 Device Driver Status:
Scsi Address
Prt :Bus :Tar :Lun Status
------------------- -----------------------------------------------
0003:0000:0003:0000 IBM ULT3580-HH4 BBH5 [IBM ULT3580-HH4 1K10121873] (White List User Mode Driver)
0003:0000:0003:0001 IBM 3573-TL B.20 [IBM 3573-TL 00X2U78R5291_LL0] (White List User Mode Driver)
9999:0112:0004:0001 FIXEDB2DDevice 1.00 [FIXEDB2DDevice {8AC8D2F1-E121-44D0-89D8-CE670AFEAE66}]
------------------- -----------------------------------------------
Scsi Address
Prt :Bus :Tar :Lun Attributes
------------------- -------------------------------------------------------------------------------
0003:0000:0003:0000 Device Name "\\.\Tape0"
Secondary Name "\\?\scsi#sequential&ven_ibm&prod_ult3580-hh4#5&3433385&1&000300#{53f5630b-b6bf-11d0-94f2-00a0c91efb8b}"
Primary Inquiry "IBM ULT3580-HH4 BBH5"
Serial Number "IBM ULT3580-HH4 1K10121873"
Device Flags UMD, SCSI, SN(TYPE 0)
Device State 3, Online
Device IDs 1021, {D762016E-D7B9-4E91-909C-0EB867EC5F7E}
Device Name "Tape drive 0001"
Device Type 134283265, "LTO 64K (64K,10,0,E,HU)"
Device Features 0x005BFA7F: PB,SFB,SRB,WFM,SFF,SRM,PEOD,EL,LU,E,SBS,DC,SDC,TA,HU,RR,W,EN
Device Element 1024, 0
Device Block Limits 512 min, 1048576 max
Device Hard Errors 2 write, 0 read
Device Soft Errors 790 write, 23 read
0003:0000:0003:0001 Device Name "\\.\MediumChanger1"
Primary Inquiry "IBM 3573-TL B.20"
Serial Number "IBM 3573-TL 00X2U78R5291_LL0"
Device Flags UMD, SCSI, SN(TYPE 0), SN(ELEMENT)
Device State 3, Online
Device IDs 1024, {E909BB03-4253-4EFA-938E-F6BA2FD267B9}
Device Name "Robotic library 0001"
Device Type 2131755008, "CHANGER FS=1"
Device Features 0x00006200: PP,RMP,RRD
1st Slot Number 1
Number Of Slots 23
Portal Slots 1
Import/Export Robotic
Drive Element 0 1021, "IBM ULT3580-HH4 1K10121873"
------------------- -------------------------------------------------------------------------------
9999:0112:0004:0001 Device Name ""
Secondary Name "\\?\Volume{ce7b9da0-7453-11e1-8b98-d4ae526e58cc}"
Primary Inquiry "FIXEDB2DDevice 1.00"
Serial Number "FIXEDB2DDevice {8AC8D2F1-E121-44D0-89D8-CE670AFEAE66}"
Device Flags SPO_B2D, LOCAL, SN(TYPE 0)
Device State 3, Online
Device IDs 1009, {8AC8D2F1-E121-44D0-89D8-CE670AFEAE66}
Device Name "Disk storage 0001"
Folder Path "E:\BEData\"
------------------- -------------------------------------------------------------------------------
[3792] 03/25/15 08:37:19.988 Start Rsm Support:
[3792] 03/25/15 08:37:20.004 Device Discovery End:
[3792] 03/25/15 08:37:20.113 Disk mapping for Win32:
Win32 name NT internal name
------------------------ -------------------------------------------------------------------------------
C: \Device\HarddiskVolume2
D: \Device\HarddiskVolume3
E: \Device\HarddiskVolume4
F: \Device\CdRom0
PhysicalDrive0 \Device\Harddisk0\DR0
Harddisk0Partition1 \Device\HarddiskVolume1
Harddisk0Partition2 \Device\HarddiskVolume2
Harddisk0Partition3 \Device\HarddiskVolume3
Harddisk0Partition4 \Device\HarddiskVolume4
------------------------ -------------------------------------------------------------------------------
[StorageManager::RemoveUnusedLocalDisksFromDB] Results:
1 non-present unconfigured local disks were deleted
1 local disk parent objects with no local disks were deleted
[6360] 03/25/15 08:38:38.804 PvlDrive::UpdateOnlineState()
Drive = 1025 "Unconfigured disk cartridge 0001"
ERROR = The device is offline!
[7000] 03/25/15 08:38:53.044 PvlDrive::UpdateOnlineState()
Drive = 1025 "Unconfigured disk cartridge 0001"
ERROR = The device is offline!
[3336] 03/26/15 17:11:45.863 The following event was reported on 3/26/2015 5:10:04 PM:
The driver detected a controller error on \Device\RaidPort1.
--------------------
This error signifies controller errors. These errors are generally caused by hardware that is not functioning correctly. To resolve these errors, try the following actions:
- Slow the SCSI bus.
- Verify that the latest SCSI drivers and firmware are loaded.
If these errors continue to occur, contact the hardware manufacturer.
[3336] 03/26/15 20:57:17.138 The following event was reported on 3/26/2015 8:49:05 PM:
The driver detected a controller error on \Device\RaidPort1.
--------------------
This error signifies controller errors. These errors are generally caused by hardware that is not functioning correctly. To resolve these errors, try the following actions:
- Slow the SCSI bus.
- Verify that the latest SCSI drivers and firmware are loaded.
If these errors continue to occur, contact the hardware manufacturer.
[3336] 03/28/15 01:31:16.113 The following event was reported on 3/28/2015 1:31:11 AM:
The driver detected a controller error on \Device\RaidPort1.
--------------------
This error signifies controller errors. These errors are generally caused by hardware that is not functioning correctly. To resolve these errors, try the following actions:
- Slow the SCSI bus.
- Verify that the latest SCSI drivers and firmware are loaded.
If these errors continue to occur, contact the hardware manufacturer.
[4008] 03/29/15 23:23:59.038 Adamm Log Stopped!
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