A Time Machine time bomb
rondam.blogspot.com
rondam.blogspot.com
I thus assume that he was using OSX on a custom-built machine and it's very well possible that OSX doesn't have built-in eSATA support (due to the lack of official hardware) and thus doesn't recognize the external drives as external ones.
You see, when I plug a USB or Firewire drive into my Mac, Time Machine doesn't try to back them up.
On my systems I also backup to a BackupPC system for longer term storage.
It's not intended to be used to retain a complete history of your machine and as such if used for this purpose you're eventually going to get a nasty surprise.
If it cannot delete anything else and the storage is beyond its limits, it e-mails me telling me to please do something about it.
Time machine is nice because its nearly impossible to remember to do backups regularly (unless it's your job) and the backups are highly available, but really its more like an extended trash bin, not an archive. Storing your backups on-site is one thing, but keeping them plugged in and mounted is just asking for it.
Whatever happened to tapes? They're like comically expensive now. Another option is to copy your Time Machine out to S3 once a month. (Would probably take that long) but I don't know how you'd preserve the aliases / hard links.
I like it so far but I don't think it solves the alias/hardlink problem, so you'd just get one or two good snapshots before it got to be really expensive. The great feature of time machine (or rsync --link-dest) is that your snapshots share storage of unchanged files, and I don't know how to make S3 do that.
Edit: This was actually a reply to duskwuff's comment.
<Begin rant> Oh jeez. I worked at a company that made tape drives and you do not want to use tapes ever. They are the slowest, most unreliable thing imaginable. Especially now that they are making them more and more dense and the media is exposed to the elements (unlike a disk platter).
Yeah, they use more redundant ECC than disks but I still wouldn't trust them at all. I had definitely drunk the kool-aid for a while and happily used tape for data transfer and not just backup. I can't tell you how many times I got stuck with a bad tape hours away (physically) from the original data, frustrated beyond belief. I firmly believe most people don't even know just how many of their tapes are corrupted because they've never tried to restore except for the initial testing period and the occasional file or two.
Tape sucks. Tape is dead. Long live disks. <end rant>
> Another option is to copy your Time Machine out to S3 once a month. (Would probably take that long) but I don't know how you'd preserve the aliases / hard links.
One of the interesting things about time machine is how it deals with network backups. It creates an HFS+ disk image on the remote machine and then mounts that and does the backup to it instead of directly to the remote volume. It uses the "sparse bundle" style disk image which partitions the disk image into a bunch of 8mb slices. So you could rsync those slices to S3 daily or monthly or whatever and not worry about the format details at all.
Hey! Let's solve a backup trimming problem by potentially never backing data up unless the user digs around in their preferences! This seems like a cure that's worse than the disease.
And by the way, I had that volume on my exclude list, but TM forgot about it. (That's a problem that has been around since TM first appeared.)
Good luck with that, and please do call us when every single kernel contributor gets sued because someone accidentally overwrites their Windows partition when installing Ubuntu.
YOU EXPRESSLY ACKNOWLEDGE AND AGREE THAT USE OF THE APPLE SOFTWARE IS AT YOUR SOLE RISK AND THAT THE ENTIRE RISK AS TO SATISFACTORY QUALITY, PERFORMANCE, ACCURACY AND EFFORT IS WITH YOU.
and
TO THE EXTENT NOT PROHIBITED BY LAW, IN NO EVENT SHALL APPLE BE LIABLE FOR...LOSS OF DATA.
and for good measure,
THE APPLE SOFTWARE IS NOT INTENDED FOR USE IN THE OPERATION OF NUCLEAR FACILITIES, AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL SYSTEMS, LIFE SUPPORT MACHINES OR OTHER EQUIPMENT IN WHICH THE FAILURE OF THE APPLE SOFTWARE COULD LEAD TO DEATH, PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE.
Bottom line is that these licenses don't mean much anyway - they just make it slightly harder to sue someone, in the same way that those personal liability forms you sign before doing anything are just to scare you. In the absence of an explicit contract - as in Apple guarantees "this will not cause any data to be deleted" - they've got a very good case that while it's sad you lost your data, it's not their fault.
Paying for something may create more of an expectation, but does not (in and of itself) guarantee you anything or increase liability.
I knew that these disclaimers were in both licenses. However I think that the fact that Linux is given away for free and that OS X is a product makes a difference in the clause TO THE EXTENT NOT PROHIBITED BY LAW. I mean, you can't buy an Apple computer without OS X on it. Are they really allowed to disclaim all liability for everything? In my legally uneducated mind that seems unlikely.
That said, maybe I've missed something in the marketing that Apple have done for the product - your comment seems to indicate that. Do you have any specific examples of false claims made in marketing TM by Apple?
Have any readers that have upgraded to OS X 10.6 experienced the same issue?
The bottom line is that Time Machine is a backup solution with a certain level of archiving as an added feature; it is not a bulletproof archival solution and shouldn't be relied on for that purpose.
Furthermore it sounds like this guy is using Time Machine as an archiving solution, not a backup solution. You shouldn't be all that worried to lose backups a year old if you know newer ones are intact. You should never delete a document there's any chance of ever needing again, then rely on TM or similar to save it for you.