Why does NetBackup Down a Tape Device?

Problem

Why does NetBackup Down a Tape Device?

Error Message

Status
******
DOWN

Cause

NetBackup will down a tape device under the following Conditions listed below:

Troubleshooting

1. NetBackup attempts to mount a tape in the drive. NetBackup send the robot a command to move the tape from one address to another. NetBackup will await the tape drive to show SCSI Ready status. This can be seen the vmoprcmd output where write is enabled and Ready is enabled. When the tape drive shows a SCSI Ready status it will report the tape HEADER information and NetBackup verify the correct tape is in the correct drive. When there is a tape already in the drive NetBackup cannot complete the tape mount. This shows as a status 98 TPreq error. Since NetBackup cannot use this drive for backup NetBackup will down the device.

Example output from vmoprcmd command showing SCSI Ready:

                                 DRIVE STATUS

Drive Name               Label   Ready  RecMID  ExtMID  Wr.Enbl.  Type    Host             DrivePath                            Status
=============================================================================
QUANTUM.SDLT600.000      Yes     Yes    LT01S3          Yes       dlt    sludge_win_bmr    {1,0,2,0}                       TLD

Exact error code 98 TPReq error shown from Event Viewer > Application.

2004/09/02 5:18:04 NetBackup TL4 Daemon Error None 9760 N/A SYS-SEC-DB            TL4(0) [1380] Move_medium error

The robtest command is located in the volmgr/bin directory or the Hardware Vendors Web Interface can be used to remove stuck tapes.

Example output from robtest command:

C:\Program Files\Veritas\Volmgr\bin>robtest
Configured robots with local control supporting test utilities:
 TLD(0)     robotic path = {1,0,1,0}

Robot Selection
---------------
 1)  TLD 0
 2)  none/quit
Enter choice: 1
1

Robot selected: TLD(0)   robotic path = {1,0,1,0}

Invoking robotic test utility:
C:\Program Files\Veritas\Volmgr\bin\tldtest.exe -rn 0 -r {1,0,1,0}

Opening {1,0,1,0}
MODE_SENSE complete
Enter tld commands (? returns help information)
s d
drive 1 (addr 1) access = 1 Contains Cartridge = yes
Source address = 1024 (slot 1)
Barcode = SDLT01S3
drive 2 (addr 2) access = 1 Contains Cartridge = no
drive 3 (addr 3) access = 1 Contains Cartridge = no
drive 4 (addr 4) access = 1 Contains Cartridge = no
drive 5 (addr 5) access = 1 Contains Cartridge = no
drive 6 (addr 6) access = 1 Contains Cartridge = no
drive 7 (addr 7) access = 1 Contains Cartridge = no
drive 8 (addr 8) access = 1 Contains Cartridge = no
READ_ELEMENT_STATUS complete

Please see the Related Articles for further details on robtest command usage. (100016165)

2. NetBackup chooses a Tape drive and Media to use for a Backup Job. At the start of the Job NetBackup will send a SCSI Query against the tape device. If the drive returns a tape drive serial number that is not configured for the drive in question. NetBackup cannot validate that the backup information will go to the correct tape device.

NetBackup will down the tape drive path to this device on the media server. This same tape device may still work on other media server. This behavior shows this issue is limited to the NetBackup media server that the tape device path is configured on. If the media server cannot query the device either another media server has a SCSI Lock on the device or the Media server cannot talk to the drive.

The 'scan' utility will also show the output of SCSI Query to the device. The Tape drive will return the inquiry string:

Example output from the scan command:

C:\Program Files\Veritas\Volmgr\bin>scan -tape
************************************************************
*********************** SDT_TAPE    ************************
************************************************************
------------------------------------------------------------
Device Name  : "Tape7"
Passthru Name: "Tape7"
Volume Header: ""
Port: 1; Bus: 0; Target: 10; LUN: 0
Inquiry    : "SONY    SDX-900V        5400"
Vendor ID  : "SONY    "
Product ID : "SDX-900V        "
Product Rev: "5400"
Serial Number: "XYZZY_8"
WWN          : ""
WWN Id Type  : 0
Device Identifier: "SONY    SDX-900V        XYZZY_8  "
Device Type    : SDT_TAPE
NetBackup Drive Type: 18
Removable      : Yes
Device Supports: SCSI-5
Flags : 0x0
Reason: 0x0

3. NetBackup will down a tape drive if it encounters 3 device Input/Output errors within a 24 hour period.
Device I/O errors come in many different varieties and are usually an indication of a Hardware Error.
This includes TAPEALERTS, SENCE KEY ERRORS, Please Clean, Clean Now and Other hardware related issues.
This would also include any time NetBackup receives a ALERT from the tape drive.

These errors will be seen in the NetBackup Device Manager / ltid log. The ltid service by default will log in the syslog / messages on UNIX/Linux systems and Event Viewer > Application Logs on Windows systems.

The NetBackup Legacy logs bptm and bpbrm will also provide information in regards to the exact error.

Please review the NetBackup™ Logging Reference Guide for more information on how to Set the Media Manager debug logging to a higher level.

Solution

Review of the Media Manager Debug Logging will show the reason for the failure. The System Administrator can review the debug logging to see why NetBackup has Downed the Tape Device.

Once the exact error is shown in the above logs, determine the best course of action to take next.
This will include, but is not limited to:

• A. Reconfiguration of the Device with NetBackup
• B. Update of the NetBackup Device Mappings file.
• C. Update to Firmware of the Device.
• D. Update Device Driver or configuration files
• E. Tape Drive Cleaning
• F. Service the Hardware by 3rd party vendor or Replacement of the Tape Drive Unit.

Reference: NetBackup™ Device Configuration Guide