Time Machine with Iomega Home Media NHD

Hi, and welcome to the forums.

I hate to tell you this, but that is not a supported destination for Time Machine backups: http://docs.info.apple.com/article.html?path=Mac/10.6/en/15139.html

The wording is a bit confusing, but this is the relevant part:

+*If your backup disk is on a network, the network server must use Apple File Protocol (AFP) file sharing, and both your computer, and the networked backup disk, should have Mac OS X 10.5.6 or later.+*

Tiago Schmidt wrote:
. . .
So I still have one question: there is a solution for this issue? Something like use a AirPort or similiar?

The Time Capsule (combination wireless router and disk drive) was designed specifically by Apple as a destination for Time Machine backups: http://store.apple.com/us/search?find=capsule&mco=MTA4NTc4Mzc

You can also back up over a local network to a shared drive on a Mac running Leopard or Snow Leopard.

While the previous article (and others) specifically say you cannot back up to a USB drive attached to a recent Airport Extreme, many of us (including me) are doing it anyway. There's always the risk that a future update will prevent it, though.

It can be done, it just requires more effort. Apple, of course, would rather you pay for their overpriced NAS, but that shouldn't stop you.

Anyway, these guys detail how to do it with a Western Digital "My Book World Edition", but their directions should (in theory, anyway) work for any NAS device: http://forums.macosxhints.com/showthread.php?p=493450

the site of Iomega says that this issue must be solved in the new firmware:

https://iomega-na-en.custhelp.com/cgi-bin/iomegana_en.cfg/php/enduser/std_adp.php?p_faqid=21149&p_created=1231204221&p_sid=XHmAi uPj&p_accessibility=&p_redirect=&p_lva=&p_sp=cF9zcmNoPTEmcF9zb3J0X2J5PWRmbHQmcF9 ncmlkc29ydD0mcF9yb3dfY250PTEwLDEwJnBfcHJvZHM9MTAzMSwxMDQzJnBfY2F0cz0mcF9wdj0yLjE wNDMmcF9jdj0mcF9zZWFyY2hfdHlwZT1hbnN3ZXJzLnNlYXJjaF9ubCZwX3BhZ2U9MSZwX3NlYXJjaF9 0ZXh0PXRpbWUgbWFjaGluZQ**&p_li=&ptopview=1

Is this correct? I want to buy this HDD with my new Macbook Pro.

Hi, and welcome to the forums.

If you do, you do it at your own risk. Yes, Iomega claims it's compatible with TIme Machine (but requires some extra feature from Iomega).

But read this carefully: http://docs.info.apple.com/article.html?path=Mac/10.6/en/15139.html

If the Iomega doesn't fit that definition exactly, Apple will not support this.

From a post in another forum (found by V.K.):

The technical reason why Apple limits Time Machine to 10.5 AFP volumes appears to be to prevent disk image corruption. There were additional features added to AFP in 10.5 to support Time Machine. These presumably allow the disk image engine to force disk image journal data to write out all the way to the disk. Without such features, a network interruption can result in a corrupted filesystem on the disk image despite journaling. Remember, journaling relies on the journal being written all the way to disk before the changes take place. If you can't guarantee that (e.g., because of network/NAS buffering) then the journal is useless. Time Machine appears to rely heavily on disk journaling to deal with network drop-outs, interrupted backups, and the like. Take this away and your data is at risk.

If the NAS you are using supports these features it should report them to the OS and you should natively be able to choose that volume. If you have to trick the OS to use the volume it means the NAS does not support it.

To summarize: if you care about your backup data you should avoid using non-natively supported AFP servers.

That post obviously applies to Leopard; Snow Leopard appears to have added some requirements, that are also not supported by all NAS devices, and some that were working with Leopard no longer work with Snow Leopard.

Requiring another software package may let most of the TM operations work, but you probably cannot do a full system restore from those backups.
That is done using the installer on the Snow Leopard Install disc, which will not have that package on it.
See #14 in the Frequently Asked Questions *User Tip,* also at the top of this forum.

It's your call, of course, but I would NEVER trust my backups to such a scheme.