Tape and Tape Devices Troubleshooting

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Tape and tape devices issues

Problem with tape drives

Problem

  • There are problems with LTO tape drives which repeatedly request cleaning tape. Additionally, backups fail with I/O errors.

Solution

There are two possible causes for this:

  • SEP sesam has problems communicating properly with tape devices if hardware vendor's tape diagnostic tools are still installed after the tape read/write diagnostic test is successful. To stop the tape drives from repeatedly issuing the cleaning request and ensure that backups successfully complete, remove the tape diagnostic tools immediately after the diagnostic tests are complete. For example, there are some problems with different tape drives LTO5 and LTO7. In our example, you will disable or remove the following components:
  1. Disable HPE Version Control Agent.
  2. Disable all tape agents for HPE Insight Management Agents as shown below.
  3. HPE Insight-disable tape agent.jpg

  4. Uninstall HP Library and Tape Tools (L&TT) from your server by using the Add/Remove Program in the Window's Control Panel.
  • Similar issues may be caused by common hardware-related problems. Refer to your hardware vendor documentation for details about hardware configuration and troubleshooting.

Restore fails due to a missing block that was not written to tape, but no error is generated during backup

Problem

  • (Applies only to Windows SEP sesam Server or RDS, ≤ SEP sesam Beefalo V2) When backing up to tape, a data block is not written to tape when the segment size is reached at End of Media (EOM), therefore a restore of data referencing this block is not possible. While a Path Archive can still be restored until EOM is reached, a complete restore or migration will fail.

Solution:

  1. Detect whether your tapes are affected by following the procedure How to detect affected savesets below.
  2. Update your Windows SEP sesam Server with a fix for Beefalo V2. If your tape device is attached to a Windows RDS, you have to install the update to the respective RDS.

How to detect affected savesets

The following steps must be executed on your SEP sesam Server.

  1. Check the path behind the variable gv_rw_lis in sm.ini to see if your LIS folder's destination was changed. Example with modified LIS folder – set to D:\SEPsesam\var\lis\:
  2. [PATHES]
    gv_rw_lis=D:\SEPsesam\var\lis\
    
  3. Open the command prompt ('Windows Command Processor' or Linux 'Terminal') and issue the following commands. Change to the directory of your LIS folder according to sm.ini gv_rw_lis=... :
    • Windows (default): C:\ProgramData\SEPsesam\var\lis
    • cd C:\ProgramData\SEPsesam\var\lis
      findstr /R /C:"^.*:.*:0:.*:1$" *.sgm
      
    • Linux (default): /var/opt/sesam/var/lis
    • cd /var/opt/sesam/var/lis
      grep "^.*:.*:0:.*:1$" *.sgm
      
  4. If the command retrieves some lines then inspect the related sgm files. In the following example, the third line (marked in red) shows an occurrence of a lost block.
  5. 1:140479734912:1088:MP_File_Full00001:38956
    1:143030262144:1089:MP_File_Full00001:48605
    1:146212528704:0:MP_File_Full00010:1
    10:146212594176:1:MP_File_Full00010:55536
    

    The third line shows the following: On tape with ID 1: there are 146212528704 bytes written, but then it shows the segment 0 that is not a real segment number but caused by error, ending by :1 block that is actually lost.

See also

Managing Devices and Media