INFO: Max Target File Size Registry Key

UBQ ID Number: UBQ000166

Last Modified: 2001-03-13 at 10:42:48

SUMMARY:

On some systems such as certain types of Linux or Unix (most notably on the Linux systems that exist on drives like Maxtor and SNAP drives), there is a file size limitation that if a backup goes above that size, the backup fails.  

DETAILS:

On some systems such as certain types of Linux or Unix (most notably on the Linux systems that exist on drives like Maxtor and SNAP drives), there is a file size limitation that if a backup goes above that size, the backup fails.  On those systems, UltraBac needs to be set manually to limit the size of the backup files.

To do this, the registry must be modified to access the feature, as the following:

HKEY_LOCAL_MACHINE/Software/BEI/UltraBac/

Create a value named: MaximumDiskBackupFilesize:REG_DWORD 

Normally this is set to 0 which means "no limit". Otherwise, the number represents the file size in bytes that each sub-file should be limited to.  To limit the output file size to 512 MB, select 'Hex', and enter the number "20000000".  In Decimal, this number would be '536870912'.

What this means: On Linux/Unix machines files can only be a max size of 2GB. If you are targeting a disk drive on a Unix machine and the backup for any particular set is larger than 2GB then this will be a problem. The work around is to use the registry entry above. What will happen instead of the contents of a directory of a targeted disk backup looking like:

08/16/2000
08/16/2000
08/16/2000
08/16/2000

05:01p
05:19p
05:19p
05:19p

32,768
2,633,629,696
32,768
0

 _ub_back.001
 _ub_back.002
 _ub_back.003
 _ub_back.004

 

The second file is larger than 2GB so it would be broken up into files like: (assuming the registry entry was 2000000000)

08/16/2000
08/16/2000
08/16/2000
08/16/2000
08/16/2000

05:01p
05:19p
05:19p
05:19p
05:19p

32,768
2,000,000,000
633,629,696
32,768
0

  _ub_back.001
  _ub_back.002
  _ub_back.002_000
  _ub_back.003
  _ub_back.004

 

This registry entry prevents files getting too big on the output, so when the .002 file for example gets to be too big, a new file with a filename of .002_000 is opened to continue the backup. This is because some file systems (such as fat32) don't permit files greater than 4GB in size and Unix doesn't permit files greater than 2GB in size, so you can set this to 1GB or whatever you want....

You must use UltraBac 5.53 or later to have this functionality.

MORE INFORMATION:

See UBQ: UBQ000031 – Registry Keys

See UBQ: UBQ000041 – Selecting a Storage Device

See UBQ: UBQ000049 – Defining a Disk (disk-path) Storage Device

See UBQ: UBQ000156 – UltraBac Specific Hidden Registry Keys

CATEGORIES:

Configuration/Administration, Registry, Restore

VERSION:

UltraBac versions 5.53 and later

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