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PachiPachi's avatar
PachiPachi
Level 3
10 years ago

Restore Error, Maximum Block size

Hello,

 

I am trying to do a restore from an LTO4 tape with a Quantum i2k .The backup was written with this library and media server 4 years ago but now doing a restore is resulting in this error:

1/05/2015 13:11:53 - Error bptm(pid=10204) The tape device at index 3 has a maximum block size of 524288 bytes, a buffer size of 1048576 cannot be used
21/05/2015 13:11:55 - Error bptm(pid=5068) The following files/folders were not restored:      

 

I have changed the SIZE_DATA_BUFFERS to 524288 and tried 262144 but it isnt seeming to be taking affect on the restore,it keeps resulting in the same error.I am sure the file is spelt and syntaxed correctly .Its definately on the correct media server too.Anything else I can do to enforce it for this restore?.

NBU: 7.5.0.4

Windows 2008 R2

Please let me know if you require further information.I am sure am just missing something small.

 

  • Changing the block size won't help, that is only for backup.   For restore, the BS used is what ever was used for backup, it cannot be changed.

    The issue is the drive - it cannot read a blocksize of 1024 , it's max limit is 512k.

    Only option is to find a drive that can, nothing can be done from NBU, as it's not actually a NBU issue.

    * The HBA can also have this limitation, not sure if you get the same error message though.

  • Changing the block size won't help, that is only for backup.   For restore, the BS used is what ever was used for backup, it cannot be changed.

    The issue is the drive - it cannot read a blocksize of 1024 , it's max limit is 512k.

    Only option is to find a drive that can, nothing can be done from NBU, as it's not actually a NBU issue.

    * The HBA can also have this limitation, not sure if you get the same error message though.

  • Martin is the expert here !

    My addition to Martins post:

    Netbackup uses a automatic block detection mechanism - SIZE_DATA_BUFFERS is only used for setting the backup block size. Without the block detection it could not say "1048576" buffer size is required :-)

  • Yup thanks for the replies chaps!,much appreciated.As he said that I changed the media server to be used in the restore to our Master server which has access to the tape library as well.Just with a different HBA ,that Allowed me to do the restore,so its probably the HBA on the other media server causing it,

    Thanks for the help!