[CorpITGuy]

My wife uses a MBP and I have a Dell that runs Vista. We have a single 500GB hard drive and would like to back up our data to it. I used the out-of-the-box format for the disk (whatever it was) and copied all my files. When my wife tries, it gives her two errors on her MBP: (1) Permissions error (says she needs read/write priveleges, which Get Info says she has) and (2) file names are too long.

I presume this is a formatting error. If so, how should I re-format the disk? More to the point, what format should I use in Disk utility.

[DigitalEl]

More than a day with no answer. I'm watching this thread, too.

I imagine lots of people upgrading to Leopard will be buying external drives in order to take advantage of Time Machine.

I bought a Seagate FreeAgent drive. 250 GB for about $65 at Best Buy. Out of the box, it's formatted for Windows and I get that I need to use Disk Utility to reformat, but do I use:

Mac OS Extended (Journaled)
Mac OS Extended
Mac OS Extended (Case-sensitive, Journaled)
Mac OS Extended (Case-sensitive)

I bought this drive for the singular purpose of using Time Machine. How do I format?

[peeb]

I's most likely formatted for NTFS, which Apples can read, but not write.

Mac OS extended (journalled) is what you want - it's the default, but bear in mind your windows machine will not be able to read that.

The only format both can read (without other software) is FAT32. That has file size and name limitations.
One way to deal with this if you must share the drive is to use a network share.

[reader50]

Drives from the factory are usually formatted FAT32. Later windows versions default to NTFS, which OSX only enables Read access to. At least, as of Tiger. I haven't heard if Leopard enables full Write access, or formatting ability.

Time Machine in Leopard requires the backup drive to be formatted HFS+, and Windows doesn't provide native support for that disk format. If you want an external drive to work with Time Machine, you'll have to go the HFS+ route and pick up one of the 3rd party utilities that lets Windows access HFS+ volumes.

If you want dual access to an external drive, and won't use it for Time Machine, then reformat it to FAT32 using Disk Utility on the Mac. It should recognize and work on both platforms then.

For a drive intended for Mac use, you get the four choices shown in the above post. Ignore the (Case-sensitive) options, enabling case sensitivity is just a nuisance. It can trip up older applications too, I'd imagine.

If you need full compatibility for the drive with Mac OS9, then choose regular HFS+. The same goes if you are using an OSX version in the 10.0 - 10.2 range. Otherwise, chose HFS+ Journaled. The earlier OSs don't know how to maintain the Journal file, which forces the later OSX versions to rebuild the file on a regular basis.

HFS+ Journalled disks start up way faster after a kernel panic or other unexpected shutdown (power failure, etc). The Journal file records recent filesystem changes, after an unexpected shutdown, the journal file is replayed to the last known stable configuration and bootup continues.

With a 500 GB drive, that shortens the next reboot down to a few seconds delay to fix the boot disk up. Without the journal, the entire boot disk has to be checked with fsck before bootup can finish. That could take minutes ... or an hour, depending on how fast your computer is.

Time Machine should work with any of the HFS+ variants listed. The only gotcha that I can think of is if your main Mac disk enabled case sensitivity, I'd think the Time Machine disk would need it too.

note: HFS+ is another name for "Mac OS Extended"

[DigitalEl]

Thanks for the thorough explanation. I'm going with the basic "Mac OS Extended (Journaled)." I'm ready for Leopard.