Hello,

I wanted to buy a 'Western Digital My Passport Essential USB 2 320 GB' hard drive to be used on a Mac with Time Machine, and permanently. Does this work?

I have the same one for the PC and just tried connecting it to the Mac; it worked immediately, Time Machine offered to use it as Backup drive (and noted I would have to reformat it, from NTFS to HFS+ Journaled).

I always thought PC and Mac hard drives would be identical by hardware, and that only the file systems would be different. However, Western Digital produces another hard drive called "My Passport Essential for Mac", which costs 35-50% more (and has a silver design). I wonder, being one of the only external hard drives offered in retail Apple Stores (at least in Germany), if they only produce this so Apple has something explicitly Mac-formatted to sell, as there is HFS+ Journaled already.
Googling, you find various notes; from the PC drive simply being Mac compatible, to the PC drive being incompatible to Time Machine according to the Western Digital website, as it is not the official Mac version.

Huh? Trying to save this money, I would guess it simply works. (?)

Greetings,
Pete

[P]

It should work if you reformat it. I use a WD Mybook drive for Time Machine. They sell a Mac version of that as well (with FW support), but I use the "Windows version" with no problems.

Is it this drive? If so, it's even officially supported.

[moonmonkey]

Yes, it will work Perfectly.

Originally Posted by P 

It should work if you reformat it. I use a WD Mybook drive for Time Machine. They sell a Mac version of that as well (with FW support), but I use the "Windows version" with no problems. 

Is it this drive? If so, it's even officially supported.

Yes, that's the one! (Although the 320 GB version, but even nearly identical product number). That's so confusing, on this page they say it's going to work.

But here, they say it won't... But apparently, it will be ok.

[Thorzdad]

The Passport Essential comes formatted NTFS, and will need reformatting for Mac compatibility. Their specification PDF says as much.

[eyadams]

It may also be necessary to re-partition the drive, especially if you get the Windows version. That's in addition to re-formatting. I bought a drive that would work until the computer went to sleep, and then the drive wouldn't mount, and Disk Utility couldn't do anything with it. The problem turned out to be that it used the wrong partitioning scheme.

[P]

Originally Posted by eyadams 

It may also be necessary to re-partition the drive, especially if you get the Windows version. That's in addition to re-formatting. I bought a drive that would work until the computer went to sleep, and then the drive wouldn't mount, and Disk Utility couldn't do anything with it. The problem turned out to be that it used the wrong partitioning scheme.

That should not be required unless you're trying to boot from the drive. Strange.

(If someone would like to correct our terminology here and explain what reformatting, repartitioning and making a new filesystem really means, then... just go away. We know what we mean.)

[jmiddel]

Isn't partitioning the only way to reformat? There is no 'Reformat' option in DU, only 'Erase' and 'Partition', the latter giving the option of reformatting as well.

The way I understand the terms is that Reformat is erasing all data and installing a file system, Partitioning entails erasing all data and giving us the option to break the drive up into more than one volume, during which operation you have to choose a filesystem, of course on Macs HFS+ is the default. I hope I'm not off base here

[moonmonkey]

Originally Posted by jmiddel 

Isn't partitioning the only way to reformat? There is no 'Reformat' option in DU, only 'Erase' and 'Partition', the latter giving the option of reformatting as well.
The way I understand the terms is that Reformat is erasing all data and installing a file system, Partitioning entails erasing all data and giving us the option to break the drive up into more than one volume, during which operation you have to choose a filesystem, of course on Macs HFS+ is the default. I hope I'm not off base here

Erase is 'Apple' for Reformat.
You can chose Mac OS Extended Journaled when you erase.

Originally Posted by P 

That should not be required unless you're trying to boot from the drive. Strange.

(If someone would like to correct our terminology here and explain what reformatting, repartitioning and making a new filesystem really means, then... just go away. We know what we mean.)

Well, thanks for the help, obviously... It was great so far, always wondering and it's good to prepare everything before trying something new. I don't know if I really understand this part of the debate, though. As for me, I would say I'm not sure what is really meant by partitioning scheme. I would have simply used 'Erase' and gone for HFS+ Journaled, being the current OS X filesystem; nothing too fancy around here, it would be great if it would mount, too, hmm :-) And it's not used to boot from, so...

[P]

I probably confused everyone with that comment. The old term "formatting" referred to a very low-level process that is not required these days - all HDs arrive formatted and should not be reformatted. That term has then been reused to mean either writing a new file system or deleting the partition map, neither of which is really correct.

If you select the hardware disk in Disk Utility, you can select "Erase" - which will remove all partitions and just make one big new partition, with a file system on it - and "Partition", which will let you make several partitions as you like with filesystems on. If you select a partition and select that same "Erase", it just makes a new file system without changing the partition scheme. What you usually need to do is only the last thing - make a new file system on an existing partition, and not touch the partition map. eyeadams' comment is that that is not enough - you also need to repartition, because the partition map is in the wrong format. The partition map format is relevant when booting from a drive, but when the booting is done, the OS should know enough to recognize all partition map formats.

Originally Posted by P 

I probably confused everyone with that comment. The old term "formatting" referred to a very low-level process that is not required these days - all HDs arrive formatted and should not be reformatted. That term has then been reused to mean either writing a new file system or deleting the partition map, neither of which is really correct.

If you select the hardware disk in Disk Utility, you can select "Erase" - which will remove all partitions and just make one big new partition, with a file system on it - and "Partition", which will let you make several partitions as you like with filesystems on. If you select a partition and select that same "Erase", it just makes a new file system without changing the partition scheme. What you usually need to do is only the last thing - make a new file system on an existing partition, and not touch the partition map. eyeadams' comment is that that is not enough - you also need to repartition, because the partition map is in the wrong format. The partition map format is relevant when booting from a drive, but when the booting is done, the OS should know enough to recognize all partition map formats.

Alright, thanks! That's the clarification I needed.
So I think I'm going to get this drive, it looks great so far, there's also 'stiftung warentest' in Germany, a renowned German test magazine that often does 'European' tests with other magazine of various things (everything from multimedia to more everyday stuff, but even the more technical tests are usually pretty good, informative and reliable). Well, they thought the WD drive was really good, too, even as it apparently consumes not so much energy and that's something. Thanks for all the help, so far!

[Eug]

I wouldn't recommend the My Passport for a desktop computer. That's a slow laptop drive that's USB powered, built for portability.

For a permanent Time Machine drive for a desktop (iMac / Mac mini), I'd get a desktop backup drive. Much better € to GB ratio. Faster too, and very noticeably so if you ever have to move large amounts of data to/from it.

---

The Mac versions of WD drives are the same drives, just formatted with HFS+. I never buy the Mac versions because they cost more, around here at least. If I buy a WD external drive, and I do own the My Passport for portability, I always buy the PC version and reformat it.

[jmiddel]

P said: probably confused everyone with that comment. The old term "formatting" referred to a very low-level process that is not required these days - all HDs arrive formatted and should not be reformatted. That term has then been reused to mean either writing a new file system or deleting the partition map, neither of which is really correct.

According to Wikipedia: 'the term "format" is understood to mean an operation in which a new disk medium is fully prepared to store files' . So, to do so, the disk medium has to be organized according to the needed file format. This is low level, yet is something we Mac users have to do with the drives we buy, because they all are formatted the Microsoft way. There is no neutral formatting, it's either HFS+, FAT or something else, so when I buy a new HD, my Mac just asks me whether I want to initialize it, which I do.

[P]

The Wikipedia page in question is actually quite good:


Quote:

Formatting a disk for use by an operating system and its applications involves three different steps.

1. Low-level formatting (i.e., closest to the hardware) marks the surfaces of the disks with markers indicating the start of a recording block (typically today called sector markers) and other information like block CRC to be used later, in normal operations, by the disk controller to read or write data. This is intended to be the permanent foundation of the disk, and is often completed at the factory.
2. Partitioning creates data structures needed by the operating system. This level of formatting often includes checking for defective tracks or defective sectors.
3. High-level formatting creates the file system format within the structure of the intermediate-level formatting. This formatting includes the data structures used by the OS to identify the logical drive or partition's contents). This may occur during operating system installation, or when adding a new disk. Disk and distributed file system may specify an optional boot block, and/or various volume and directory information for the operating system.

And further down:


Quote:

The present ambiguity in the term <i style="font-family: sans-serif; line-height: 19px; text-align: -webkit-auto; ">low-level format[/I] seems to be due to both inconsistent documentation on web sites and the belief by many users that any process below a high-level (file system) format must be called a <i style="font-family: sans-serif; line-height: 19px; text-align: -webkit-auto; ">low-level[/I] format. Since much of the low level formatting process can today only be performed at the factory, various drive manufacturers describe reinitialization software as LLF utilities on their web sites.

Formatting used to mean only step 1 above, but since that is generally not done at the consumer level any more, the term has shifted to include either or both of the later steps. Apple avoids the term completely, and "Erase" in disk utility means either 2 and 3 or just 3 depending on what you have selected.

So: The formatting of type 1 in the list above does not have to be done. Formatting of type 3 - making a new file system - definitely has to be done for a PC-formatted drive. The question was if formatting of type 2 needs to be done. In my experience no, but eyadams had a different experience and recommends that you do it. The reason then would be that Windows generally uses a partition map of type MBR (Master Boot Record) while Macs these days use maps of type GPT (GUID Partition Table) and used to use Apple Partition Map.

Originally Posted by Eug 

I wouldn't recommend the My Passport for a desktop computer. That's a slow laptop drive that's USB powered, built for portability.
For a permanent Time Machine drive for a desktop (iMac / Mac mini), I'd get a desktop backup drive. Much better € to GB ratio. Faster too, and very noticeably so if you ever have to move large amounts of data to/from it.
---
The Mac versions of WD drives are the same drives, just formatted with HFS+. I never buy the Mac versions because they cost more, around here at least. If I buy a WD external drive, and I do own the My Passport for portability, I always buy the PC version and reformat it.

Alright, thanks for the reply! A few questions, though: I thought even 2.5" USB 2 drives reach about 20MB/sec and often enough even more, is that so bad? Isn't that enough? I thought it would be ok for most things. I just feels right to me to have a small backup drive somewhere that looks after the Time Machine backups, but still thinking about these things...
Something else: Do you really notice the difference with too slow/fast enough/somewhat average with Time Machine? I thought it work rather work on in the background all of the time, with the very rare exceptions of spantenous change in data volume, very huge data transfers, no? I thought it would be hardly noticeable, but don't know yet, still preparing, you see... This is not about movie editing or anything...

[jmiddel]

Speed is not that essential for backing up, which can run at night, or with TM it happens in the background.