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schalliol · Mar 27, 2010, 09:41 PM

Early in FileVault's history, I heard reports of some data loss, and under 10.5.0 there were Time Machine issues. Assuming you don't forget the password, is there any downside of using FileVault other than a very slight performance degradation? I've used encrypted sparsebundles for the rare times I need to have some tax ids and account numbers, but many documents and would benefit from encryption in case a machine was stolen.

Basically, someone talk me out of turning it on...

imitchellg5 · Mar 27, 2010, 09:57 PM

From what I've heard it eats up massive amounts of hard disk space. Maybe someone else can comment.

schalliol · Mar 27, 2010, 10:27 PM

Hmm, that's interesting. I just went to click on it and was told that if I turned on FileVault that it would only backup via Time Machine when the account is logged out and I can't restore a single file (only a massive wipe and replace). These do seems like pretty big taxes for using FileVault. It might be worth doing. Right now I have open firmware password, password on wake and Orbicule's Undercover, but none of that will really protect the data.

mduell · Mar 27, 2010, 11:35 PM

The "no TM backups while you're logged in" issue is fatal.

Goldfinger · Mar 28, 2010, 04:26 PM

To be honest I think that FileVault was a pretty useless feature from the beginning. There are more downsides to it than upsides. The Time Machine thing is very annoying. It will probably back up your entire home dir again and again, resulting in a huge and very slow backup every time. I won't do incremental backups since FileVault is essentially a disk image so TM sees it as one big file. (someone correct me if I'm wrong, but I'm pretty sure that's how it works). Also, if your FileVault image gets corrupted you lose your entire home folder.

Do you really need to encrypt everything in your home directory ? Why not make an encrypted (or multiple) disk image for those sensitive files. If you really need everything encryped then you'll just need to live with the downsides.

Spheric Harlot · Mar 28, 2010, 04:31 PM

FileVault is a solution only where a total loss of data is preferable to someone else gaining access to it.

Art Vandelay · Mar 28, 2010, 05:22 PM

Originally Posted by Goldfinger

It won't do incremental backups since FileVault is essentially a disk image so TM sees it as one big file. (someone correct me if I'm wrong, but I'm pretty sure that's how it works).

No, starting with 10.5, FileVault uses a sparse bundle disk image. Sparse bundle disk images are comprised of disk image segments. So if you change one file, only the segment that contains the file will be backed up.

Goldfinger · Mar 28, 2010, 05:51 PM

Originally Posted by Art Vandelay

No, starting with 10.5, FileVault uses a sparse bundle disk image. Sparse bundle disk images are comprised of disk image segments. So if you change one file, only the segment that contains the file will be backed up.

Right, didn't know that sparsebundle images were built like that. Thanks for the info.

schalliol · Mar 28, 2010, 09:09 PM

I decided to go ahead and go for it. The encryption didn't take that long initially, though it's taking an eternity (estimated 24 hours) to do the initial 200GB backup over gigabit ethernet while logged out. I saw that there's a way to hack the system to allow backup while logged in, but there are some downsides of doing that. I'll report back with my findings!