Source:Troubleshooting Tape and Tape Devices

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 the hardware vendor's tape diagnostic tools are still installed after the tape read/write diagnostic test is successful. To prevent the tape drives from repeatedly issuing the cleaning request and ensure that backups complete successfully, remove the tape diagnostic tools immediately after completing the diagnostic tests. For example, there are some problems with the different tape drives LTO5 and LTO7. In our example, you will disable or remove the following components:

1. Disable the HPE Version Control Agent.
2. Disable all tape agents for HPE Insight Management Agents as shown below.

1. Uninstall HP Library and Tape Tools (L&TT) from your server 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 on 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 the tape when the segment size is reached at the End of Media (EOM), therefore restoring data referencing this block is not possible. A path archive can still be restored until EOM is reached, but a complete restore or migration fails.

⇒ Solution:

1. Detect whether your tapes are affected by following the procedure How to detect affected savesets below.

1. Update your Windows SEP sesam Server to a newer version. 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\:

 [PATHES]
 gv_rw_lis=D:\SEPsesam\var\lis\

2. Open the command prompt ('Windows Command Processor' or Linux 'Terminal') and enter 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

3. If the command retrieves some lines, check the related sgm files. In the following example, the third line (marked red) shows an occurrence of a lost block.

    1:140479734912:1088:MP_File_Full00001:38956
    1:143030262144:1089:MP_File_Full00001:48605
    <span style="color:red">1:146212528704:0:MP_File_Full00010:1</span>
    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.

Problems with LTO-9 tapes

Error loading new LTO-9 tape

Problem

SEP sesam is unable to load a new LTO-9 tape into a tape drive. When uncalibrated LTO-9 tapes are inserted into a library, they cannot be moved into the drive. During archive adjustment, SEP sesam identifies the slots containing such media and marks them with an orange indicator to signal that tape initialization is required.

Cause

Some tape libraries (for example, HPE MSL2024 up to G3, 1/8 G2 Autoloader, and similar) do not allow loading a non-calibrated LTO-9 tape media into a tape drive. This prevents accidental loading of non-calibrated tapes into the drive and helps prevent possible backup issues while a new LTO-9 tape initialization is in progress.

For more information, see HPE Support Center: LTO-9 Media initialization.

⇒ Solution:

For such libraries, use New Media Initialization Wizard to perform the new LTO-9 tape initialization.

Note that the initialization process for a tape can take between 20 minutes and up to 2 hours. In most cases it will complete within 30 minutes for a tape, however, in some cases it may take up to two hours. After start the initialization process cannot be aborted.

Limited or no access to new LTO-9 tapes

Problem

When introducing new LTO-9 tapes, SEP sesam may encounter access issues, time-outs or backup delays because of ongoing LTO-9 tape initialization.

Cause

Some tape libraries (for example, HPE StoreEver MSL6480, and similar) allow moving a non-calibrated LTO-9 tape media into a tape drive, but start the initialization process before the tape can be first used. In this case SEP sesam may encounter issues with backup because of ongoing LTO-9 tape initialization.

⇒ Solution:

LTO-9 tapes require one-time media initialization before read/write operations can first be started. In most cases this initialization process will complete within 30 minutes for a tape, however, in some cases it may take up to two hours. Note that after start the initialization process cannot be aborted.

To prevent issues with delayed or failed backups to new LTO-9 tapes, it is recommended to initialize the new LTO-9 tape using archive adjustment with the Automatic introduction option. This starts the media initialization before first use.

It is important that you do not use the option Adjustment by barcode only when running archive adjustment. This option collects barcodes for slots without moving the tape into the drive. Therefore, media initialization is not performed during archive adjustment. Instead, it will start the first time the tape is used.

Alternatively, you can use New Media Initialization Wizard to perform the new LTO-9 tape initialization before using it with SEP sesam.

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