# Firewire HDs, Transfer Limit 2G



## pki51 (Dec 18, 2004)

Howdy,
I have two, 120G firewire, external HDs, installed and partitioned using OS 9. They have a limitation on the size of transferring files, stopping at 2G (or so) with an error message. Files UNDER 2Gs transfer flawlessly. I'm running OS X 10.3.3. Is there a setting that can be changed to address this issue? The drives are master and slave and I'm stopped from reformatting only the empty one. I assume I'll have to reformat both of them. Most of the files are video files, don't compress much, and are larger than the two gig limit. Any ideas? 
Thanks, pki


----------



## YeeFam (Nov 19, 2004)

I formatted my firewire drive using OS X - forgot the exact wording but something + journaled. I was running OS X 10.3.6.

I then attached it to a OS 9.2 and used it - I put about 48 GB on it for as part of our testing and encountered no problems. I also analyzed the data on the OS X -


----------



## YeeFam (Nov 19, 2004)

OS X File System:	Journaled HFS+

Not sure if this helps - but it is worth a try


----------



## YeeFam (Nov 19, 2004)

*File Size Max is 2^63 - bit more then 4GB*

HFS+ is architecturally similar to HFS, with several important improvements such as

32 bits used for allocation blocks (instead of 16). HFS divides the disk space on a partition into equal-sized allocation-blocks. Since 16 bits are used to refer to an allocation-block, there can be at most 216 allocation blocks on an HFS filesystem. Thus, using 32 bits for identifying allocation blocks results in much less wasted space (and more files).

Long file names up to 255 characters

Unicode based file name encoding

File/Directory attributes can be extended in future (as opposed to being fixed size)

In addition to a System Folder ID (for starting Apple operating systems), a dedicated startup file that can easily be found (its location and size are stored in the volume header in a fixed location) during startup, is also supported so that non-Apple systems can boot from a HFS+ filesystem

Largest file size is 2^63 bytes


----------



## shuuhen (Sep 4, 2004)

What are the drives formatted as? You can check with Get Info. As YeeFam said, HFS+ has a file size limit of 2^63 bytes. With HFS+ you shouldn't have issues transfering 2 GB files. HFS has a file size limit of 2^31 bytes, which could cause the error with transfering 2+ GB files.

Most of the time you will want to use HFS+. HFS is usually only needed for some really old Macs (They can only run up to Mac OS 8.1).

There is a nice comparison chart here.


With two separate drives, you should be able to format only one (or one at a time). If you continue to have issues formatting only one of them at a time, try leaving the drive you do not want to format disconnected while you format the other.

If you need them, there are utilities that can convert HFS drives to HFS+. PlusMaker is the only one I can think of, but there might be others.


----------

