Dell NetWorker 19.9 Administration Guide

Block-size incompatibility between UNIX and Windows

Incompatible block-size settings between UNIX and Microsoft Windows storage nodes could result in any of these error scenarios:

• A backup taken on a UNIX node might not be recoverable on a Microsoft Windows node if the Windows node does not support large block sizes.
• A UNIX process labels and saves data to a tape and leaves the tape mounted. A Microsoft Windows process subsequently attempts to verify the label on this tape and fails because the label verification is done by reading a header from the data portion.
• A tape on a UNIX node is labeled with a large block size. The backup is started on a Microsoft Windows node and the Windows node attempts to write the backup by using the default block size. Internally, the backup on Windows is written by breaking down the big buffer of data into smaller segments of writable block sizes.

  Attempting to recover a specific file on Windows in this situation fails due to positioning errors on the tape. The data is still recoverable from the Windows side, since the NetWorker software will switch from using file and block positioning to reading the tape from the beginning to reach the correct position. The data might not, however, be recoverable from the UNIX side.