Time Machine...why bother?

[lssmit02]

Time Machine not archiving/versioning software

Part of the disappointment with TM may be that some see it as a form of archiving or versioning software. However, as I now see it, TM's primary function is to provide you with a backup of your drive that is as close to up to date as can be when your computer crashes. Hence, the hourly backups. Secondarily, it provides deletion protection, but not complete deletion protection (as fully described above). I have to admit, I did not really understand that this is how TM worked. But for most users, that's not a problem because most people create files, and then never delete them. Given that deletion protection is TM's secondary function, that's alright.

This is not to say that Apple has made this distinction clear.

 

[danny_w]

Part of the disappointment with TM may be that some see it as a form of archiving or versioning software. However, as I now see it, TM's primary function is to provide you with a backup of your drive that is as close to up to date as can be when your computer crashes. Hence, the hourly backups. Secondarily, it provides deletion protection, but not complete deletion protection (as fully described above). I have to admit, I did not really understand that this is how TM worked. But for most users, that's not a problem because most people create files, and then never delete them. Given that deletion protection is TM's secondary function, that's alright.

This is not to say that Apple has made this distinction clear.

But since Apple specifically advertises TM as deletion protection in the virtual tour, I'm afraid it is going to catch a lot of people off guard when they go back to look for a file that they deleted (accidentally or otherwise) and find that it is not there. Deletion protection is certainly not secondary in Apple's advertisement of the product.

 

[lssmit02]

But since Apple specifically advertises TM as deletion protection in the virtual tour, I'm afraid it is going to catch a lot of people off guard when they go back to look for a file that they deleted (accidentally or otherwise) and find that it is not there. Deletion protection is certainly not secondary in Apple's advertisement of the product.

Agreed. I certainly did not understand this. However, since most people create, but never delete (guilty), probably it's not a big issue. However, for those counting on TM to provide a form of archiving, they will be surprised to learn about how TM works.

 

[cmaier]

If TM is doing hourly backups, then I'd kind of expect a file I create and delete later in the day, to be included in a daily backup. That looks like it's not the case though.

-Kevin

That seems to be a weird expectation. If the file was deleted during day X, I wouldn't expect it to be in day X's backup, even if it did appear in an hourly backup during that day.

It seems you are expecting TM to be versioning. not backup, software. Go download cvs or something if you want every version of every file to be around forever, whether you delete it or not.

 

[netnothing]

That seems to be a weird expectation. If the file was deleted during day X, I wouldn't expect it to be in day X's backup, even if it did appear in an hourly backup during that day.

It seems you are expecting TM to be versioning. not backup, software. Go download cvs or something if you want every version of every file to be around forever, whether you delete it or not.

I understand Apple's way of thinking. I guess what a lot of people were hoping was that instead of simply making a Daily backup from a single hourly snapshot, TM would merge all the changes in the hourlies for that day, and make that the Daily backup. I mean after all, the file has already been copied to the drive.

I know that's probably asking a lot, but it'd be nice to have.

I'm not expecting every version of every file to be available so relax.

I think the gotcha in all this is.....if a file ends up in an hourly backup, people will tend to assume it gets into a daily backup. That's not the case.

It would be nice if Apple could do a little better in creating the Daily backups. I mean c'mon, taking a single hourly backup as the Daily? At least compare the first and last and merge those.

As someone posted on the Apple support boards:

Files created

1) lasting less than 1 hr will NOT be backed up, period...

2) lasting longer than an hour BUT less than a day, will be deleted after 24 hrs when yesterday's backups are 'thinned'

3) lasting longer than a day BUT less than a week, will be deleted after 1 month when the previous month's are 'thinned'

So... it seems that only files lasting longer than 1 week will remain on the drive permanently (barring the need to 'thin' for space reasons)

-Kevin

 

[saltyzoo]

Time machine does an excellent job at taking a time consuming, painful, boring, and confusing task and making it quick, painless, exciting, and keeping the confusion just for fun.

Seriously though, the design is a quantum leap ahead of any alternative for the average numbskull that's never backed anything up before.

 

[cmaier]

I understand Apple's way of thinking. I guess what a lot of people were hoping was that instead of simply making a Daily backup from a single hourly snapshot, TM would merge all the changes in the hourlies for that day, and make that the Daily backup. I mean after all, the file has already been copied to the drive.

I know that's probably asking a lot, but it'd be nice to have.

I'm not expecting every version of every file to be available so relax.

I think the gotcha in all this is.....if a file ends up in an hourly backup, people will tend to assume it gets into a daily backup. That's not the case.

It would be nice if Apple could do a little better in creating the Daily backups. I mean c'mon, taking a single hourly backup as the Daily? At least compare the first and last and merge those.

As someone posted on the Apple support boards:



-Kevin

Sorry, I still don't get your complaint. I would expect a "daily backup" to be a backup of the disk at the time the daily backup is taken. Not a weird almagamation of all of the hourly backups that occurred during that day. Same with weekly, monthly, etc.

In other words, to me (and, i think, most people who do their own backups), all backups are snapshots of the system taken at regular intervals, and the difference between daily and hourly is that hourlies get deleted more frequently to free up space (or tapes, or cd's, orwhatever the medium is). There's no magical meaning to "daily" beyond the fact that it lives longer.

Heck, the *last thing I want* is for it to include files I deleted before the backup was taken. That would be incredibly confusing - you think you got rid of something prior to the daily backup, you do a restore, and it comes back! All the files you thought were temporary and never wanted to see again make a reappearance. yuck.

 

[netnothing]

Sorry, I still don't get your complaint. I would expect a "daily backup" to be a backup of the disk at the time the daily backup is taken. Not a weird almagamation of all of the hourly backups that occurred during that day. Same with weekly, monthly, etc.

In other words, to me (and, i think, most people who do their own backups), all backups are snapshots of the system taken at regular intervals, and the difference between daily and hourly is that hourlies get deleted more frequently to free up space (or tapes, or cd's, orwhatever the medium is). There's no magical meaning to "daily" beyond the fact that it lives longer.

Heck, the *last thing I want* is for it to include files I deleted before the backup was taken. That would be incredibly confusing - you think you got rid of something prior to the daily backup, you do a restore, and it comes back! All the files you thought were temporary and never wanted to see again make a reappearance. yuck.

I agree...and your last paragraph makes sense...completely.

However, to me, it comes from the old way of thinking about backups in that....you mainly use them to restore your entire system.

What Apple has done is given the ability, mainly through the interface, to just go in a pick files from here and there. While I agree that IF you were to restore from a Daily in this case using my thinking of TM, then yes, it would be annoying to have all those files back.

I still think that the most reliable backups for full system restores are things like SuperDuper and CCC. And I am waiting to hear reports of how well TM does with restoring a new system from scratch.

I guess in this case Apple is correct in it's thinking.

I am curious though.....which is better, making the Daily backup from the first backup of the day, or the last?

-Kevin

 

[danny_w]

Sorry, I still don't get your complaint. I would expect a "daily backup" to be a backup of the disk at the time the daily backup is taken. Not a weird almagamation of all of the hourly backups that occurred during that day. Same with weekly, monthly, etc.

In other words, to me (and, i think, most people who do their own backups), all backups are snapshots of the system taken at regular intervals, and the difference between daily and hourly is that hourlies get deleted more frequently to free up space (or tapes, or cd's, orwhatever the medium is). There's no magical meaning to "daily" beyond the fact that it lives longer.

Heck, the *last thing I want* is for it to include files I deleted before the backup was taken. That would be incredibly confusing - you think you got rid of something prior to the daily backup, you do a restore, and it comes back! All the files you thought were temporary and never wanted to see again make a reappearance. yuck.

But that is EXACTLY what Apple is claiming that TM does in their virtual tour. By your argument, no file that is deleted will ever be available at a later date, because WHENEVER you delete a file it is not going to be in the daily backup. It WILL be in the previous daily backup, but the next weekly backup will cause that backup to get purged. After a month and all evidence of the file is now gone. Not exactly what they are advertising...

"Every hour, every day, an incremental backup of your Mac is made automatically as long as your backup drive is attached to your Mac. Time Machine saves the hourly backups for the past 24 hours, daily backups for the past month, and weekly backups for everything older than a month. Only files created and then deleted before the next hourly backup will not be included in the long term. Put another way: You’re well covered."

 

[wyatt23]

Sorry if this has been brought up. Am I the only one that doesn't really care about the Time Machine feature? I do video and film work and have been fine without it all these years. I backup regularly and feel very comfortable with my workflows. Suddenly it seems like every other post here is about...

"I gotta get a new external drive for Time Machine, can't wait!"

It just seems to me that Time Machine will only make people lazy. I can't justify getting a whole new drive for such a feature. I didn't need it before, why should I need it now?

anything that can make me a little lazier... i say bring it on. quit beefing with TM.

 

[benpatient]

cmaier, i have to completely disagree with you 100%.

If you are working on a file, the chances are that you are working on it within the span of a week's time in almost all cases. Say you're writing a paper for school, ok?

It's in your "Documents" folder, and you finish the paper through the course of a couple of days. You print it out and turn it in.

Then at the end of the semester, your professor asks you for another—digital this time—copy of that paper to use as an example for the next semester, because it was just so awesome (or bad).

But you accidentally deleted that file along with some other things you didn't think you'd need in your "documents" folder.

This is exactly the same kind of situation the guy in the "guided tour" describes as being Time Machine's greatest power.

And yet if you had the misfortune of writing, saving, printing, and deleting that paper within a week's time that didn't include a weekly snapshot from TM, then you are screwed.

Now take the same situation but instead of a professor, try it with your boss and an expense report, or a client and a series of product design concepts.

Most people don't delete things from their machines EVER simply because they are afraid to do so in case they might need something again in the future. They just leave it there. They don't do a backup, so they have a fear of deleting something. I know lots of times I get on someone's computer and they have several GB of files in their trash/recycle bins built up from years of being afraid of pushing the big "empty" button.

But when you tell someone to go buy an external hard drive, plug it in, and never lose a file again...that frees them from the fear of deleting things...

Apple says:
"Only files created and then deleted before the next hourly backup will not be included in the long term. Put another way: You’re well covered."

That will encourage people like my parents to finally empty their trash can. Can you imagine me explaining the technical reasons of why their files really WERE deleted? because they moved them to the trash before the Wednesday night backup, or whenever it is?

I'm having a hard time thinking of a situation where TM would reliably save me from making a mistake...I rarely work on a project for more than a week. It's just the nature of a production environment...

 

[cmaier]

But that is EXACTLY what Apple is claiming that TM does in their virtual tour. By your argument, no file that is deleted will ever be available at a later date, because WHENEVER you delete a file it is not going to be in the daily backup. It WILL be in the previous daily backup, but the next weekly backup will cause that backup to get purged. After a month and all evidence of the file is now gone. Not exactly what they are advertising...

"Every hour, every day, an incremental backup of your Mac is made automatically as long as your backup drive is attached to your Mac. Time Machine saves the hourly backups for the past 24 hours, daily backups for the past month, and weekly backups for everything older than a month. Only files created and then deleted before the next hourly backup will not be included in the long term. Put another way: You’re well covered."

Think of it this way. Say I create a file. I delete it an hour later. I create it again, with different data. Delete it again. I do this all day. I delete it again.

Which version do you think should be in the daily?

Similarly, instead of deleting it, I just change the data in it every hour. I add a paragraph. I delete it. Etc. What ends up in the daily?

I do NOT want the daily trying to figure out what version of my file, or filesystem, is "best." I want it to take periodic snapshots.

If I want file versioning, I use cvs or imanage.

 

[saltyzoo]

Honestly, how difficult could it be re recreate and how important could the file be if it only existed on your disk for < 1 hour? Same question < 1 day.

It's playing the odds. Yeah, not every file will be around forever, but the longer a file is on your disc the more likely it is going to be needed. Likewise, the reverse is true. The shorter it's on your disc, the less likely it's that important / difficult to recreate.

The concept of actually keeping every file ever created is a little impractical and not really necessary.

This product does a great job of protecting the average person.

 

[danny_w]

If TM is doing hourly backups, then I'd kind of expect a file I create and delete later in the day, to be included in a daily backup. That looks like it's not the case though.

-Kevin

Your assumption is to be expected. According to Apple's own description of TM, if the file is in an hourly backup then it will be available forever. This is clearly not the case.

 

[saltyzoo]

Your assumption is to be expected. According to Apple's own description of TM, if the file is in an hourly backup then it will be available forever. This is clearly not the case.

That would be hourly backups as long as disk space lasts. On the application screen it clearly says hourly for 24 hours, daily for 1 week, etc...

Frankly, nobody would use this if it were hourly forever. It's not practical.

 

[andiwm2003]

the more i hear about time machine the less interested i get.

i do a superduper clone of my hd everytime i think i have enough new data (weekly or so). that is for quick restore in case a hd dies.

and files i want to keep forever get a version number and go into an archive folder. that is for having important files forever.

then i have an external hd at home and every now and then i clone it to an off site hd (in case my house burns down with all in it).

so far two of my HD's died and i never lost any data.

the whole process takes me 10 min hands on time every week or so.

in addition i burn my iphoto library to dvd every now and then just to be safe.

no i don't think i need time machine.

 

[madmaxmedia]

Your assumption is to be expected. According to Apple's own description of TM, if the file is in an hourly backup then it will be available forever. This is clearly not the case.

They don't explicitly state that it will be available forever, but they should be more explicit in their description:

Only files created and then deleted before the next hourly backup will not be included in the long term. Put another way: You’re well covered.

I don't equate 'long term' with 'forever'. But long term is vague (it really has to be because how long something is kept depends on your usage and the size of your original and Time Machine hard drives.)

I'm not exactly sure what Time Machine keeps as the daily backup- does it pick some arbitrary timed backup (say 2 PM) every day? I'm not sure anyone here really understand the guts well enough to know what goes on.

How many times has someone CREATED an important file, then accidentally deleted it within that day? But then you don't actually realize what you did, or even need the file in the next 24 hours?

I mean, you can create arbitrary scenarios that will defeat just about any backup/ versioning system. At the end of the day, Time Machine is FAR better than what 99% of what the total Mac userbase has in place. Most people don't back up AT ALL, and most of the rest just do occasional backups without any sort of versioning.

Other than that, I think we need more specific information about how the backups are done, and exactly what is kept in the daily and weekly backups.

 

[netnothing]

I'm not exactly sure what Time Machine keeps as the daily backup- does it pick some arbitrary timed backup (say 2 PM) every day? I'm not sure anyone here really understand the guts well enough to know what goes on.

In my case, I think TM uses the first hourly snapshot of the day (taken shorty after midnight) as the Daily backup for the day.

Why do I think this....2 reasons:

1) If you look at the timeline in TM (or on your disk), you'll notice that your firs hourly backup of the day stays there all day long. TM deletes the other hourly backups first.

2) When I create a file on 10/31 at 10am.....it was not in the daily backup for 10/31. Because, I think, it used the hourly backup from 12:22a.

-Kevin

 

[todd2000]

I think this quote finally made it somewhat clear for me, I was under the impression that it took all the hourly backups and merged them into the daily, but from what im reading it just takes the first hourly backup from the day and makes it the daily?? That doesn't make any sense.

Files created

1) lasting less than 1 hr will NOT be backed up, period...

2) lasting longer than an hour BUT less than a day, will be deleted after 24 hrs when yesterday's backups are 'thinned'

3) lasting longer than a day BUT less than a week, will be deleted after 1 month when the previous month's are 'thinned'

So... it seems that only files lasting longer than 1 week will remain on the drive permanently (barring the need to 'thin' for space reasons)

Honestly for what I use Backup for, (Mostly iPhoto, and iTunes, and my Home Directory) this should work fine. I rarely have files on my computer that last less then a week, and if I delete them before a week I probably didn't need them anyway.

I think TM will work ok for me, but Im debating if I should just go back to using CCC to clone my drive on Mon, Wed, and Thur like I used to?? I can't quite decide, although thinking about it, I was just cloning my drive 3 times a week, no incremental, or anything, just making a new clone every time. SO technically TM is better then my previous backup strategy.

 

[cmaier]

I think this quote finally made it somewhat clear for me, I was under the impression that it took all the hourly backups and merged them into the daily, but from what im reading it just takes the first hourly backup from the day and makes it the daily?? That doesn't make any sense.



Honestly for what I use Backup for, (Mostly iPhoto, and iTunes, and my Home Directory) this should work fine. I rarely have files on my computer that last less then a week, and if I delete them before a week I probably didn't need them anyway.

I think TM will work ok for me, but Im debating if I should just go back to using CCC to clone my drive on Mon, Wed, and Thur like I used to?? I can't quite decide

How on earth could it "merge" the hourlies into a daily? A particular file might have 24 different hourly versions - what would the daily look like in that case?

 

[Phil A.]

But that is EXACTLY what Apple is claiming that TM does in their virtual tour. By your argument, no file that is deleted will ever be available at a later date, because WHENEVER you delete a file it is not going to be in the daily backup. It WILL be in the previous daily backup, but the next weekly backup will cause that backup to get purged. After a month and all evidence of the file is now gone. Not exactly what they are advertising...

"Every hour, every day, an incremental backup of your Mac is made automatically as long as your backup drive is attached to your Mac. Time Machine saves the hourly backups for the past 24 hours, daily backups for the past month, and weekly backups for everything older than a month. Only files created and then deleted before the next hourly backup will not be included in the long term. Put another way: You’re well covered."

Time machine works exactly as they are advertising: If you delete a file it will disappear from the daily backups after a month (not a week) but will still be in the weekly backup until you run out of space
Put another way, the amount of time you have to get a file back after you have deleted it depends on how long it existed on your disk after you created it before you deleted it:
Less than an hour: Forget it
An Hour: 1 Day
A Day: 1 Month
A Week: As long as you have space on your disk

It seems to me as if this is a pretty comprehensive backup system and probably more comprehensive than 95% of existing ones: I used Super Duper onto 2 disks before Time Machine. This only gave me a daily snapshot every day so anything I created and deleted in a day would be gone forever and anything that got deleted would be gone 2 days later: What Time Machine gives me is far in excess of this...

 

[Antares]

To me, Time Machine makes sense:

The hourly backup is a snapshot of the computer at the exact moment the hourly backup is run.
The daily backup is a snapshot of the computer at the exact moment the daily backup is run (or the first hourly backup is saved as the daily backup).
The weekly backup is a snapshot of the computer at the exact moment the weekly backup is run (or the first daily backup is saved as the weekly backup).
The monthly backup is a snapshot of the computer at the exact moment the monthly backup is run (or the first weekly backup is saved as the monthly backup).

Think logically about this....the only files that will be backed up are the ones that exist when the backup is run...not files that are created after the last backup but are deleted before the next backup. If a file is not backed up, how can you expect to restore it? Essentially, you have a day to restore any file that you deleted/lost/modified in the previous day. For storage space reasons, after that, Time machine only keeps one of the hourly snapshots (not sure if it is the last or first snapshot of the day..) and so on for weekly and monthly, etc. as time goes on.

What some people seem to want is for all hourly backups to be saved forever. That means never having a daily, weekly or monthly backup. What would be the point of those if all hourly backups are kept? Unfortunately, HD space is not infinite and saving all hourly backups is not practical.

For future versions of Time Machine, I can see Apple allowing users to select how many days hourly backups are kept, how many weeks daily backups are kept, how many months weekly backups are kept, etc.. Storage space would then be the only true limiting factor. As far as I know, the current version of Time Machine doesn't give these options...and that is what I think people are really complaining about. But I think a future update of Time Machine will eventually alleviate this. People, the current Time Machine is a great start and it will only improve.

 

[netnothing]

How on earth could it "merge" the hourlies into a daily? A particular file might have 24 different hourly versions - what would the daily look like in that case?

Merge meaning, take all the files that were changed, created, added and take the most recent.

We aren't talking version control here.

People I'm sure would be happy with just the most recent of the day.

-Kevin

 

[Phil A.]

Merge meaning, take all the files that were changed, created, added and take the most recent.

We aren't talking version control here.

People I'm sure would be happy with just the most recent of the day.

-Kevin

If you have a hard disk crash you will get back the most recent of the day and the most recent will be rolled into the daily, etc.
What people are getting wound up about is if someone accidentally deletes a file and then wants to get it back.
Normally if you delete a file you've been working on a lot in a day it's an obvious mistake and you can simply retrieve it from the trash can. If you've emptied the trash can then you have 24 hours to realise your mistake and get it back. If you wait longer than that you can get changes made up until the previous daily backup for a month and the previous month for as long as you have disk space.
This only affects changes to files caused by user activity in deleting and emptying the trash can. To me this is a bonus over and above the primary use of Time Machine which is to protect your machine against hard disk failure, etc: In that instance I know I will lose an hours work at most and I would hazard a guess that that's far, far better then any backup system used by 99.9% of Mac (or PC) users.

 

[netnothing]

I'm guessing then (because I haven't been running TM for a week yet), that it will take the latest Daily backup, and make that the Weekly backup? Same for Monthly and Yearly?

-Kevin