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ntbackup.exe backing up large files

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G3rtech

Technical User
Mar 7, 2003
313
US
Has anyone ever had issues with backing up files that are 300gig plus? For some reason these files fail backup but the other smaller files complete successfully. I've checked the permissions they are ok and the file system is NTFS. I heard that Fat32 has a size limit.

Thanks!!

Gary L. Smith
Systems Technician
Guardian Manufacturing
Cocoa, FL 32926
 
The following limitations exist using the FAT32 file system with Windows operating systems:
Clusters cannot be 64 kilobytes (KB) or larger. If clusters were 64 KB or larger, some programs (such as Setup programs) might calculate disk space incorrectly.
A volume must contain at least 65,527 clusters to use the FAT32 file system. You cannot increase the cluster size on a volume using the FAT32 file system so that it ends up with less than 65,527 clusters.
The maximum possible number of clusters on a volume using the FAT32 file system is 268,435,445. With a maximum of 32 KB per cluster with space for the file allocation table (FAT), this equates to a maximum disk size of approximately 8 terabytes (TB).
The ScanDisk tool included with Microsoft Windows 95 and Microsoft Windows 98 is a 16-bit program. Such programs have a single memory block maximum allocation size of 16 MB less 64 KB. Therefore, The Windows 95 or Windows 98 ScanDisk tool cannot process volumes using the FAT32 file system that have a FAT larger than 16 MB less 64 KB in size. A FAT entry on a volume using the FAT32 file system uses 4 bytes, so ScanDisk cannot process the FAT on a volume using the FAT32 file system that defines more than 4,177,920 clusters (including the two reserved clusters). Including the FATs themselves, this works out, at the maximum of 32 KB per cluster, to a volume size of 127.53 gigabytes (GB).
You cannot decrease the cluster size on a volume using the FAT32 file system so that the FAT ends up larger than 16 MB less 64 KB in size.
You cannot format a volume larger than 32 GB in size using the FAT32 file system in Windows 2000. The Windows 2000 FastFAT driver can mount and support volumes larger than 32 GB that use the FAT32 file system (subject to the other limits), but you cannot create one using the Format tool. This behavior is by design. If you need to create a volume larger than 32 GB, use the NTFS file system instead.
NOTE: When attempting to format a FAT32 partition larger than 32 GB, the format fails near the end of the process with the following error

Tom
 
300G is a pretty big file. What are you backing up to? You doing this over a network?
 
I'm trying to backup to a 1 terabyte USB external drive and yes it's going across a small internal LAN. Usually late at night so there's not much LAN traffic.

Gary L. Smith
Systems Technician
Guardian Manufacturing
Cocoa, FL 32926
 
so you're all NTFS, you're going over a LAN. Fast Ethernet? Gb?
Your USB drive, is it 2.0 or 3.0?

I'd plug the external directly into the box you're trying to back up. That's a huge file and moving it through your network is probably what kills it.



 
So why are you using NTBackup instead of just using robocopy to copy the files to your USB disk?
 
Ok we tried plugging the USB drive directly into the server thus taking the network architecture out of the picture. It still fails. I was wondering is there any way to segment the file into pieces and back it up like that?

My company prefers that I use this backup method.


Gary L. Smith
Systems Technician
Guardian Manufacturing
Cocoa, FL 32926
 
Re-reading the threads, you haven't mentioned if you are getting any errors (just mentioning that it's not working). Have you checked the event logs, have you enabled ntbackup with logging and verified the log to see what may be the cause of your issue.
 
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