If your tape drive or library is not functioning properly, this can cause the BRU interface to report what appear to be odd errors. Since BRU uses OS X's built in SCSI layer for tape and library control, we are very dependent on that layer working properly. Check that you can communicate properly with your tape and/or library.
A good test to check BRU Server's operation is to create and execute a small backup job to your stage disk. Start by checking your stage path either using the Preferences panel in the GUI Console or by executing:
show parm stage_directory from either of the command line tools.
If the stage path is correct, open the BRU Server GUI Console and click the “New...” button. Use the following settings:
• Job Name: “Disk Test” • Destination: Stage Disk • Backup Type: Full • Job Type: Backup • Compression: Enabled
Select a few files and save the job. Answer No to scheduling and then Click the “Run Now” button to kick off the backup test. Once completed, you may delete the “Disk Test” job from the job list.
If this backup test completes successfully then BRU is working properly. This suggests that any problems are most likely related to a hardware problem.
Under Linux, check that the devices are properly recognized: # cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 01 Lun: 00
Vendor: EXABYTE Model: EXB-220 Rev: 6.04
Type: Medium Changer ANSI SCSI revision: 02 Host: scsi0 Channel: 00 Id: 02 Lun: 00
Vendor: EXABYTE Model: EXB-89008E00012F Rev: V41b
Type: Sequential-Access ANSI SCSI revision: 02 Host: scsi0 Channel: 00 Id: 03 Lun: 00
Vendor: EXABYTE Model: EXB-89008E00012F Rev: V41b
Type: Sequential-Access ANSI SCSI revision: 02 Check that the devices are seen by your Mac OS X system:
$ tapectl display Available Tape Devices: ntape0: EXABYTE VXA-2 1005
Of course, your drive info may differ, but, if instead of output similar to what you see above, you see simply:
$ tapectl display Available Tape Devices:
You definitely have a problem with your system recognizing the tape drive. Normally, BRU will recognize any tape device attached to your Mac via either the SCSI, Fibre-Channel, Firewire, or USB interfaces.
Checking your library is similar: $ libctl display
Available Tape Changers:
changer0: EXABYTE Exabyte EZ17 1.11
In either case, If you do not see a device listed, please power down the system and the drive, disconnect the tape drive from the system and double check all of your connections. A bad cable, terminator, or an incorrectly seated SCSI or Fibre-Channel card can result in a communication failure.
NOTE: Under Mac OS X, BRU uses the device names returned by the display commands above as the device names for your tape drive(s) and library. By default device numbering starts at 0 (zero) - the first tape drive would be ntape0 while the first library would be changer0. Also, even though your tape drive(s) may be inside of your library, the tape drive(s) and library robot are different devices.
If you can see the drive, but BRU Server fails when trying to write or read data, check the cabling as above (look for bent pins on SCSI cables). Also, if you are using OS X 10.2.6+, you may need to look for updated SCSI HBA drivers - Check with your SCSI vendor. On a Linux system, make sure that the “SCSI Generic” kernel driver is loaded (look for ‘sg‘ in the lsmod output). If it is not loaded, BRU Server will not be able to communicate with your devices. To manually load the driver use:
sudo /sbin/modprobe sg
We strongly recommend that you make this module a permanent part of your Linux system startup. This is usually part of your default initrd ramdisk. For information on updating the contents of your default initrd, refer to your Linux distribution’s documentation and/or the mkinitrd manpage. You may also try modifying your SCSI card settings - on the ATTO UL3 and UL4 cards, you should disable tagged command queuing and set the sync rate for the tape drive (and library) to 40MB/sec (40ST). For Adaptec AIC7XXX HBA’s under Linux, you may need to disable Domain Validation. For Mac OS X, you should also examine your System Profiler output to ensure that your SCSI adapter and attached devices are seen. SCSI and Fibre-Channel Tape drives and libraries should appear as "IOSCSIParallelDevice" entries under 10.2, and as SCSI entries under 10.3 or 10.4. Firewire and USB tape drives will show up as Firewire or USB devices.
Most connectivity problems are corrected by either performing the SCSI HBA changes mentioned or by replacing the cables and/or terminators.
If you can see the drive(s) and libraries using the steps above, but you still get errors in BRU Server when accessing the devices, the following sequence of tapectl or mt commands will test actual system communication with your drive:
Under Mac OS X:
$ tapectl -v -f ntape0 status
Vendor = EXABYTE , Model = VXA-2 Revision Level = 1005
No barcode support
Medium Type: 0x82 (loaded)
Density Code: 0x81 - VXA-2 or DLT 15GB comp BlockSize: 131072
Under Linux:
$ mt -f /dev/nst0 status SCSI 2 tape drive:
File number=0, block number=0, partition=0.
Tape block size 0 bytes. Density code 0x27 (Exabyte Mammoth). Soft error count since last status=0
General status bits on (41010000): BOT ONLINE IM_REP_EN
If this looks correct, you may test motion commands: Under Mac OS X:
$ tapectl -f ntape0 rewind $ echo $? 0 Under Linux: $ mt -f /dev/nst0 rewind $ echo $? 0
If the echo command returns anything other than zero, you have an issue with the tape drive and motion commands.
You can test library commands using libctl or mtx. Under Mac OS X:
$ libctl -v -f changer0 status
Vendor = EXABYTE , Model = Exabyte EZ17 Revision Level = 1.11
No barcode support
Robots: 1 (86), Drives: 1 (82), Tape Slots: 7 (1 - 7), No Import/Export slots. Drive 0: Full : Tape From Slot 1
Slot 1: Empty
Slot 2: Full : Ready : No Bar Code Slot 3: Full : Ready : No Bar Code Slot 4: Full : Ready : No Bar Code Slot 5: Full : Ready : No Bar Code Slot 6: Full : Ready : No Bar Code Slot 7: Full : Ready : No Bar Code
Under Linux:
$ mtx -f /dev/sg0 status
Storage Changer /dev/sg0:2 Drives, 21 Slots ( 0 Import/Export )
Data Transfer Element 0:Full (Storage Element 17 Loaded):VolumeTag = B0000001 Data Transfer Element 1:Empty
Storage Element 1:Full
Storage Element 2:Full :VolumeTag=A0000007 Storage Element 3:Full :VolumeTag=B0000007 Storage Element 4:Full :VolumeTag=A0000006 Storage Element 5:Full :VolumeTag=B0000005 Storage Element 6:Full :VolumeTag=B0000010 Storage Element 7:Full :VolumeTag=B0000009 Storage Element 8:Full :VolumeTag=A0000009 Storage Element 9:Full :VolumeTag=A0000008 Storage Element 10:Full :VolumeTag=A0000005 Storage Element 11:Full :VolumeTag=A0000010 Storage Element 12:Full :VolumeTag=B0000006 Storage Element 13:Full :VolumeTag=B0000002 Storage Element 14:Full :VolumeTag=B0000003 Storage Element 15:Full :VolumeTag=B0000004 Storage Element 16:Full
Storage Element 17:Empty Storage Element 18:Empty Storage Element 19:Full Storage Element 20:Empty Storage Element 21:Empty
To unload the tape from the drive and return it to the slot, you must first unload it from the tape drive and then instruct the robot to pick the tape and return it to its slot:
Under Mac OS X:
$ tapectl -f ntape0 rewoff ; libctl -f changer0 unload Under Linux:
$ mt -f /dev/nst0 rewoff ; mtx -f /dev/sg0 unload
To see that the unload is successful, use the same status commands from above: Under Mac OS X:
$ libctl -f changer0 status
Vendor = EXABYTE , Model = Exabyte EZ17 Revision Level = 1.11
No barcode support
Robots: 1 (86), Drives: 1 (82), Tape Slots: 7 (1 - 7), No Import/Export slots.
Drive 0: Empty
Slot 1: Full : Ready : No Bar Code Slot 2: Full : Ready : No Bar Code Slot 3: Full : Ready : No Bar Code Slot 4: Full : Ready : No Bar Code Slot 5: Full : Ready : No Bar Code Slot 6: Full : Ready : No Bar Code Slot 7: Full : Ready : No Bar Code Under Linux:
# mtx -f /dev/sg0 status
Storage Changer /dev/sg0:2 Drives, 21 Slots ( 0 Import/Export ) Data Transfer Element 0:Empty
Data Transfer Element 1:Empty Storage Element 1:Full
Storage Element 2:Full :VolumeTag=A0000007 Storage Element 3:Full :VolumeTag=B0000007 Storage Element 4:Full :VolumeTag=A0000006 Storage Element 5:Full :VolumeTag=B0000005 Storage Element 6:Full :VolumeTag=B0000010 Storage Element 7:Full :VolumeTag=B0000009 Storage Element 8:Full :VolumeTag=A0000009 Storage Element 9:Full :VolumeTag=A0000008 Storage Element 10:Full :VolumeTag=A0000005 Storage Element 11:Full :VolumeTag=A0000010 Storage Element 12:Full :VolumeTag=B0000006 Storage Element 13:Full :VolumeTag=B0000002 Storage Element 14:Full :VolumeTag=B0000003 Storage Element 15:Full :VolumeTag=B0000004 Storage Element 16:Full
Storage Element 17:Full :VolumeTag=B0000001 Storage Element 18:Empty
Storage Element 19:Full Storage Element 20:Empty Storage Element 21:Empty
If after running these tests you still have problems, but the tests all functioned properly, please contact TOLIS Group support with the following information:
Note: A support agreement is required for support after 30-days from the initial purchase date. OS X or Linux Version (kernel version if Linux)
Mac or PC System Type (G4, Xserve, Pentium, Opteron et al) Tape Drive Type and MFG
Library Type and MFG (if appropriate) BRU or BRU Server Version
BRU or BRU Server Serial Number
Contact Phone Number (access to the system is important) A thorough description of your issue