Data Protector - Restore / possible block size issue

Hi,

I’m after some advice on the following issue,

Due to migration activities of DP we need to restore data to another backup solution. During this process a multipathing driver needed to be installed onto the media agent server which appears to have caused problems with backing up and restoring.

After some testing it appears that when performing a new backup and restore it now only works with 64(kb) block size configured on the drive whereas before the driver install it was 256(kb), this means all existing restores are failing to run with the following error message:    (I’m assuming the driver install possibly changed something to lock DP to work with 64(kb) block size maximum)

[Major] From: RMA@*************  "HP:Ultrium 6-SCSI_4"  Time: 18/01/2024 10:21:31

[90:52]     Tape5:1:0:7:0C

      Cannot read from device ([87] The parameter is incorrect. )

[Major] From: RMA@*************  "HP:Ultrium 6-SCSI_4"  Time: 18/01/2024 10:21:31

[90:53]     Tape5:1:0:7:0C

      Cannot seek to requested position (Details unknown.)

[Critical] From: RMA@************* ""  Time: 18/01/2024 10:21:31

[61:17112] Medium header verification failed on drive HP:Ultrium 6-SCSI_4.

      All objects on this medium will be marked as failed.

 Data Protector version: 10.60 / Server windows 2012

Any suggestions on what could fix this issue?

  • 0  

    If only 64k works then the installd driver must be causing this and that is a real concern. If you confirm that even trying to read with 256k from a tape which was written with that blocksize is failing then my suggestion would be to use  another media agent which does not have that driver installed. Hopefully you have another system which can be used for that purpose?

  • 0

    unfortunately we don't have a spare media agent server, after checking driver install dates, the tape drives and medium changer drivers have the install date the same day the multipathing driver was installed although the drivers are still from 2013. And yes its failing to read 256k even though the tapes were originally 256k, it only works if we use 64k now. 

  • Verified Answer

    +1

    Issue resolved, had to modify registry setting for the emulex LimTransferSize (parameter) service from 1 (64kb) to 3 (256kb).

  • 0   in reply to 

    Can you please post the registry you have modified, please ?

    I am having the same issue with an HPE qlogic HBA on a windows server and in the past I simply set the registry key:

    \\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ql2300\Parameters\Device

    setting MaximumSGList to 257 to set a 1024k block size but unfortunaltely this time it is not working so I want to try your solution.

    Thaks a lot

    Dionisio Sciascia
    Micro Focus (now OpenText) Professional Services Senior Technical Consultant
    Although I am an OpenText employee, I am speaking for myself and not for OpenText.
    If you found this post useful, give it a “Like” or click on "Verify Answer" under the "More" button

  • 0 in reply to   

    Not sure if it will help, I got the information from this page > windows_manual_elx.book (broadcom.com) on page 37

    you might not have the same options for the driver/service, for me its \\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\elxfc\parameters\10000000C9908A87 and 10000000C9908A86 modifying the parameter LimTransferSize=3

    I tried the maximumSGList first with no luck then came across the above.