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Road to Mac OS X Leopard: Time Machine - Page 3

post #81 of 140
Quote:
Originally Posted by damomurf View Post

And that is where you need to be careful. Other than the amazing visual experience offered by Time Machine and the integration with individual applications, rsync is *very* much capable of achieving *exactly* the same backup strategy. Tiger already supports hard links as discussed in the article and rsync supports syncing content using hard links to avoid storing redundant copies of the same file. Sure, it's not going to be as user friendly, but it would actually work.



With rsync and hard links there would be no "restore" as such, you'd just change to a folder on your backup drive that corresponds to a backup date. That folder would appear as a full backup.

I agree that rsync isn't as good an option as Time Machine appears to be from a usability point of view - but lets not forget that it is actually capable of achieving a very similar result in terms of file storage and retrieval.

This is all correct, but somewhat beside the point. It may actually be that rsync is the engine that Time Machine uses (I don't know this and am just too lazy to try and find out right now). Apple does this often, take the existing BSD utility(s) and make it usable to the ordinary user (Activity Monitor, Disk Utility, etc.) I've used rsync and agree with you in principle but it takes either a lot of experience and/or time to get rsync to work this way reliably and with no user intervention.
post #82 of 140
One of the rumour sites spoke about Apple's portable user logins. In essence, a remote device holds all of the user data including passwords & some (or all) user files. The idea was that you could go up to any Mac's user-login screen, plug in an external device (eg iPod) and your username would appear in the user-login screen. You login with your own password, apps, files... everything.

Is it possible that a TIme Machine backup (onto a 160GB iPod, for instance) could ALSO be a portable home directory for any mac you plug into?
post #83 of 140
Quote:
Originally Posted by GregAlexander View Post

One of the rumour sites spoke about Apple's portable user logins. In essence, a remote device holds all of the user data including passwords & some (or all) user files. The idea was that you could go up to any Mac's user-login screen, plug in an external device (eg iPod) and your username would appear in the user-login screen. You login with your own password, apps, files... everything.

Is it possible that a TIme Machine backup (onto a 160GB iPod, for instance) could ALSO be a portable home directory for any mac you plug into?

The iPod is not a supported TM backup device.
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post #84 of 140
Quote:
Originally Posted by deep View Post

Seriously, you guys rock for posting these in-depth articles. Kudos to you and your team

I totally agree, excellent work Ai
post #85 of 140
Quote:
Originally Posted by Booga View Post

This is a good background article, but it misses the point of Time Machine, I think. Backing up files is old news, and I'm sure Time Machine does it as well as anyone. The real magic of Time Machine, though, is information retrieval. It's something that Shadow Copy and rsync can't hope to do.

In a traditional file backup solution, if you discover one missing record in your Address Book, you'd have to go get all your incremental backups, restore each file in turn, look for the record, and if you find it export it manually, then restore the current version and import it.

With Time Machine, you just search back through time using the same search field you do normally. It will go back in time and find the first instance of the search criteria and allow you to restore just that record to the present. THAT is revolutionary. The rest is just another implementation of an old concept.

These points were not missed, they were on the last page of the article.
post #86 of 140
Quote:
Originally Posted by khyros View Post

...snip...
b) This is about the hourly/weekly backups.

For example:

Oct 12 7pm : newly created File A is backed up to TM
Oct 12 8pm : file A was previously (7.30pm) delted so it doesn't appear on this hourly backup.
Oct 13 12am: daily backup from Oct 12 is backed up to TM. It doesn't contain file A, but file A is backed up in hourly 7pm from oct 12.

Now... a few days later, it comes the time to delete hourly backups... how does TM manage to keep file A in the TM pool for me to recover at a later time?

TM will keep your File A around for a period of 24 hr and then it will be expunged as you correctly surmised. However, if the Trash has not been emptied File A will remain in the Trash until such time you empty the Trash. Once the Trash is emptied then File A will be gone.
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post #87 of 140
Superb article. Full marks for explaining Time Machine in an understandable way and with reasonable depth.

Has anyone else noticed how well this fits with the Airport base station's ability to host a network drive. I'd think it a bit of a pain to constantly have an external hard drive plugged into my laptop (or to be plugging and unplugging all the time), but if everyone in the house was automatically backed up as soon as they arrived home, well, that's just so brilliant, and convenient!

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post #88 of 140
Quote:
Originally Posted by bxs6408 View Post

TM will keep your File A around for a period of 24 hr and then it will be expunged as you correctly surmised. However, if the Trash has not been emptied File A will remain in the Trash until such time you empty the Trash. Once the Trash is emptied then File A will be gone.

well if that's the case then TM has a serious flaw!!
for daily backups: a file won't be kept in TM if it's created and delted on the same day.
for monthly backups: a file won't be kept in TM if it's created and deleted on the same month.

This sounds all so weird and wrong to me ...
post #89 of 140
Quote:
Originally Posted by khyros View Post

This sounds all so weird and wrong to me ...

Any regular backup... if it was done at midnight daily... would miss a file that was created at 7am, and then deleted at 7pm.

However, TM will backup every hour... so you're safe there (unless created and deleted within the same hour). For a file that is months old, it's not going to keep every version of the same file... and I guess if you only have a file on your computer for 15 days, then you'll lose the file.

THis would happen on regular backup schedules too.


Anyway, overall this won't bother me as I keep files on my computer for 6 months at least... but perhaps this will bother people...
post #90 of 140
If the Mac which has created the Time Machine Backup fails and comes to the End Of It's Life.
Can you attach another Mac to that external hard drive and access those backup files without doing a system restore?
Paul
post #91 of 140
Barry,

Will TM do the same for your "BootCamp" Volume? No one seems to know. If so, I'm sold!

Bob


Quote:
Originally Posted by bxs6408 View Post

TM will restore a complete system backup and it will be bootable afterwards. Pop in the DVD Installer disc, select the Volume you wish to restore to, select the complete TM backup you want to restore from, wait for it to complete the restore operation and then you will have a bootable system once again. Works just fine, easy to do and without any real fuss.
post #92 of 140
Quote:
Originally Posted by Quarky View Post

If the Mac which has created the Time Machine Backup fails and comes to the End Of It's Life.
Can you attach another Mac to that external hard drive and access those backup files without doing a system restore?
Paul

I'm assuming you're asking if the old TM backup Volume can be used to restore its associated System and User data to your new Mac. I'm also assuming the old Mac's TM was backing up all the System and /User data. TM allows the user to exclude backing up System data. If user does so then obviously a complete System cannot be restored. When using the DVD Installer to restore from a previous TM backup only 'complete' TM backups will be listed for selection.

If the new Mac is same hardware (i.e., Old Mac was Intel-based and new Mac was Intel-based and suspect that the hardware is compatible in all respects or new Mac is simply your old Mac that has been repaired) there should not be a problem in doing this.

If the old Mac had a boot Volume name of say Quarky-HD then this Volume name will propagate to your new Mac.

Note that the TM Backup Volume you are restoring your System from must be a device that the DVD Installer can recognise. Typically this would be an external device such as USB HD or FW HD or AirDisk (and maybe network device - not sure about this though as it would depend on the network being fully functional during the early part of the DVD Installer process). Any device requiring 3rd party driver code will not be seen by the DVD Installer as it will not have the driver code to use.
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post #93 of 140
Quote:
Originally Posted by bobandris View Post

Barry,

Will TM do the same for your "BootCamp" Volume? No one seems to know. If so, I'm sold!

Bob

Interesting question. I don't know for sure - sorry.

However, even though TM, by default, excludes all volumes except the boot volume it is possible to change this. Thus if the Boot Camp Volume were named let say 'BC-HD' then user would remove BC-HD from the TM's exclusion list and allow TM to backup BC-HD.

At some later point if BC-HD failed, got corrupted suddenly or whatever, then the TM browser can be used to restore the BC-HD volume to a past time point the user felt BC-HD was in good shape such as 1 day ago or 4 days ago or 1 month ago.
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post #94 of 140
Quote:
Originally Posted by bxs6408 View Post

Interesting question. I don't know for sure - sorry.

However, even though TM, by default, excludes all volumes except the boot volume it is possible to change this. Thus if the Boot Camp Volume were named let say 'BC-HD' then user would remove BC-HD from the TM's exclusion list and allow TM to backup BC-HD.

At some later point if BC-HD failed, got corrupted suddenly or whatever, then the TM browser can be used to restore the BC-HD volume to a past time point the user felt BC-HD was in good shape such as 1 day ago or 4 days ago or 1 month ago.

First, I don't really know the answer but if TM uses FSEvents to track changes, I doubt that is will do the Boot Camp volume as it is read-only (I think this is still the case in Leopard) to OS X and therefore will show no FSEvents.
post #95 of 140
Quote:
Originally Posted by bxs6408 View Post

TM will keep your File A around for a period of 24 hr and then it will be expunged as you correctly surmised. However, if the Trash has not been emptied File A will remain in the Trash until such time you empty the Trash. Once the Trash is emptied then File A will be gone.

No way. If you create a new file, i.e., A and it is back up with Time Machine one hour and deleted within the next hour, the original back up of A is still there on the back up drive.

Best you read this article again and visit Apple's web site. A lot of questions continue to be raised and they are well answered on the two sites. Postulating on what Time Machine can or can not do by some of the meanderings here, only confuse the understanding.
post #96 of 140
Quote:
Originally Posted by AppleInsider View Post

The flip side is that some users get a backup system set in place that appears to be working, and are lulled into a false sense of security, unaware that it isn't. The faults might lie with unreliable back backup media, procedures not being carried out correctly, or the system not capturing new data it was not originally designed to protect.

Good article. I especially appreciated the discussion about 'Hard Links' and 'Soft Links'. But the article didn't address problem #2, validating the backup. Does TM know that the data got transfered to the backup ok? Or that the file in the backup is still good and hasn't gotten corrupted over time? -- For example, I rip a CD or import a photo. While I may be accessing the primary file periodically I will probably not be changing it. So after a year or so I will have a lot of hard links pointing to a single backup file. But how will I know that the data in the backup file is any good or not?
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post #97 of 140
Quote:
Originally Posted by GregAlexander View Post

Any regular backup... if it was done at midnight daily... would miss a file that was created at 7am, and then deleted at 7pm.

However, TM will backup every hour... so you're safe there (unless created and deleted within the same hour). For a file that is months old, it's not going to keep every version of the same file... and I guess if you only have a file on your computer for 15 days, then you'll lose the file.

THis would happen on regular backup schedules too.

This is so wrong! Unless of course your are doing a full back up and tossing the previous one each time. Certainly not what Time Machine is intended to do.

As the article so simply describes, connect your computer (A) to a new external drive (B) and Time Machine will open and ask you if you want to use (B) as a Time Machined backup drive. Saying yes, and Time Machine copies everything from (A) to (B).

From then on, every hour (A) is connected to (B), Time Machine (and forget how it does so for the moment), with affect every file on (A) that is different from the last back up to (B).

Time Machine does not delete a file on (B) because it was removed from (A) since the last back up, or for that matter, any other previous ones, or any in the future. It just remains on (B) to let you restore it, or any or every 'hourly' snapshot later when you may want.

If we think about it, Time Machine has not only made backing up idiot proof, it is giving us an opportunity to keep our machines lean and mean, i.e., only having the most important active files on board. And for those who like to experiment, an added comfort of going back in time to at a click of a mouse.
post #98 of 140
Quote:
Originally Posted by Abster2core View Post

No way. If you create a new file, i.e., A and it is back up with Time Machine one hour and deleted within the next hour, the original back up of A is still there on the back up drive.

Best you read this article again and visit Apple's web site. A lot of questions continue to be raised and they are well answered on the two sites. Postulating on what Time Machine can or can not do by some of the meanderings here, only confuse the understanding.


apple hasn't clarified my doubts that's why I ask here for those of you who have actually tried TM.

hourly backups are only kept for a period of time (a week?) then those are tosed and only weekly and then monthly backups are kept; all according to what i've read here and in the guide.

if file A is in the hourly backup but not on the mac's drive when the weekly/monthly backup is done, ultimately file A will be lost when hourly backups are deleted by Time Machine.

or so it seems and that's why I think it's weird...
post #99 of 140
Quote:
Originally Posted by khyros View Post

apple hasn't clarified my doubts that's why I ask here for those of you who have actually tried TM.

hourly backups are only kept for a period of time (a week?) then those are tosed and only weekly and then monthly backups are kept; all according to what i've read here and in the guide.

if file A is in the hourly backup but not on the mac's drive when the weekly/monthly backup is done, ultimately file A will be lost when hourly backups are deleted by Time Machine.

or so it seems and that's why I think it's weird...

Why do you want a backup of a file you threw away on purpose? Conversely why are you throwing away a file you want to keep? ( in your example)
post #100 of 140
Quote:
Originally Posted by Abster2core View Post

This is so wrong! Unless of course your are doing a full back up and tossing the previous one each time.

My initial impression was the same as yours - everything backed up, all older versions of the same file, etc etc.

However, it doesn't actually say that. As far as I've read (here and at Apple), Time Machine actually takes snap shots of your system. If the file is not on the system during that snapshot, then it won't be in the backup. Further, when the older daily backups are 'thrown out' leaving only monthly backups - if the file wasn't there during the monthly snapshot, it won't be in the backup.

Quote:
Originally Posted by khyros View Post

I think it's weird...

It's the same as any other backup. If you backup daily at 6pm you'll have a copy of whatever was there at 6pm that day. If at the end of the month you only keep one backup, you'll only have what was on that backup. Any version changes during the month are not kept (unless your file records version changes itself). Any file that was created one day and deleted the next is not in the end of month backups.

This is ALMOST never a problem though. How often do you need a file that you created and kept less than a month? Time Machine, afaik, is not an archive solution - it's a backup solution. If you want to get things off your hard disk when they're no longer active, you'd probably want a different program.
(edit)
ie: If you want to do a project, finish it, and then say "okay, I can delete that... it'll be in the backups"... then that's not what these backups are for. Time machine is different to taped backups because it makes it easy to get to the old info... but it's not supposed to be used as you're thinking. Think about archiving instead.
post #101 of 140
Does anyone have an idea of how TM would interact with Parallels? It would seem problematic, because whenever Parallels is active, you'd be making small changes to the virtual drive for your Parallels machine, meaning that a multi-GB file would need to be copied over every hour. Is this how it works?
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post #102 of 140
Quote:
Originally Posted by infobhan View Post

Does anyone have an idea of how TM would interact with Parallels? It would seem problematic, because whenever Parallels is active, you'd be making small changes to the virtual drive for your Parallels machine, meaning that a multi-GB file would need to be copied over every hour. Is this how it works?

If you set it to backup the virtual drive, then yeah it'd do a new file every hour. So I would presume you would simply not backup the virtual drive!!! (Perhaps Parallels will make a special service to help backup your Windows folders?).

Currently in Parallels, it has the option of using your Mac home folders as your Windows home folders... I'd suggest that you do that so it can backup your Windows files. I haven't used the latest parallels, but the old version was much slower using Mac files than the local virtual files... so for something like MS Money, I'd simply save my daily MS Money backup to the Mac folder, but leave my active database file on the virtual drive (hence not backed up).
post #103 of 140
Quote:
Originally Posted by khyros View Post

apple hasn't clarified my doubts that's why I ask here for those of you who have actually tried TM.

hourly backups are only kept for a period of time (a week?) then those are tosed and only weekly and then monthly backups are kept; all according to what i've read here and in the guide.

if file A is in the hourly backup but not on the mac's drive when the weekly/monthly backup is done, ultimately file A will be lost when hourly backups are deleted by Time Machine.

or so it seems and that's why I think it's weird...

At this time TM is tightly coupled to Address Book, Mail and iPhoto. All three employ data bases so losing an Address/contact, an Email or a photo in an Album/Event is not like deleting/losing a file. This is why TM can magically restore items for Address Book, Mail and iPhoto.

Deleting files is handled by TM as has been explained already.

Changing a byte in a data base will cause that data base to get backed up on the next TM snapshot. Deleting a byte in a data base will also have the same effect.

It will be wise to exclude the Downloads folder from backups (especially for large downloads that could takes several hours) as TM snapshots will pickup these files (or parts that have been downloaded) multiple times. Plus, typically the downloaded files get moved from the Downloads folder to other places and will subsequently get picked up again by the next TM snapshot.

If Parallels churns data in its virtual volume it will get picked every time by the TM snapshots. It will be the users choice to exclude this from TM snapshots as they wish.

TM is not your regular/traditional backup. It's a compromise between the traditional base+incremental backups and the easy data restoration, system restorations and simplified data restoration for some Applications such as Address Book, iPhoto and Mail along with keeping the amount of data backed up to be useful and of reasonable size. It could be that Apple adds others to be tightly coupled to TM. Third party Apps can also do the same thing with their Apps as Apple has done with their three Apps.

Apple wants to have TM be easy to use by Joe user who quite likely today perform no backups at all. Joe user doesn't want to understand the intricacies of backups. Just plug a 500gig HD in and turn TM on and then forget about it until the time arises to retrieve some lost data, be it a file, photo, contact, Email and even the whole complete system.

It will be of interest to see how this TM feature grows over time.
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post #104 of 140
Quote:
Originally Posted by bxs6408 View Post

At this time TM is tightly coupled to Address Book, Mail and iPhoto. All three employ data bases so losing an Address/contact, an Email or a photo in an Album/Event is not like deleting/losing a file. This is why TM can magically restore items for Address Book, Mail and iPhoto.

Deleting files is handled by TM as has been explained already.

Changing a byte in a data base will cause that data base to get backed up on the next TM snapshot. Deleting a byte in a data base will also have the same effect.

It will be wise to exclude the Downloads folder from backups (especially for large downloads that could takes several hours) as TM snapshots will pickup these files (or parts that have been downloaded) multiple times. Plus, typically the downloaded files get moved from the Downloads folder to other places and will subsequently get picked up again by the next TM snapshot.

If Parallels churns data in its virtual volume it will get picked every time by the TM snapshots. It will be the users choice to exclude this from TM snapshots as they wish.

TM is not your regular/traditional backup. It's a compromise between the traditional base+incremental backups and the easy data restoration, system restorations and simplified data restoration for some Applications such as Address Book, iPhoto and Mail along with keeping the amount of data backed up to be useful and of reasonable size. It could be that Apple adds others to be tightly coupled to TM. Third party Apps can also do the same thing with their Apps as Apple has done with their three Apps.

Apple wants to have TM be easy to use by Joe user who quite likely today perform no backups at all. Joe user doesn't want to understand the intricacies of backups. Just plug a 500gig HD in and turn TM on and then forget about it until the time arises to retrieve some lost data, be it a file, photo, contact, Email and even the whole complete system.

It will be of interest to see how this TM feature grows over time.

well let's wait for a bunch a Joe's to start complaining because they cannot go back in time and restore a file that Apple insinuated he could recover ("Go back in time to restore any file on your system").

Don't get me wrong.. TM is a great idea... but those limitations made me think. That's all.
post #105 of 140
Quote:
Originally Posted by bobandris View Post

Barry,

Will TM do the same for your "BootCamp" Volume? No one seems to know. If so, I'm sold!

Bob

Why would Time Machine work on the BootCamp Volume? That Volume could be FreeBSD, OpenBSD, Linux, Windows XP, etc., with myriad of filesystems.

This would be something I'd never expect have backed up,
post #106 of 140
I read all the replies and an interesting discussion is going on. I do agree that complaints are probably coming if John user cannot restore a specific file because it is not in his monthly backup, since Steve so deliberately stressed this as a feature. On the other hand, how often is it going to happen? People do not very often delete files for over a month and then suddenly remember that they need it again I think. And Apple does not say 'you can delete all your files, because they will be in your backup...'

Then 2 questions:
1. Asked before: will there be any way to purge a file from the TM system. Waiting for over a month would probably do the trick, but I can image that someone would like to swipe away confidential files somewhat quicker (like the minutes of an illegal syndicate made on your macbook )
2. It is clear that TM will work with an airport extreme and a connected drive. But will it work with an airport express as well?
post #107 of 140
Quote:
Originally Posted by bxs6408 View Post

At this time TM is tightly coupled to Address Book, Mail and iPhoto. All three employ data bases so losing an Address/contact, an Email or a photo in an Album/Event is not like deleting/losing a file. This is why TM can magically restore items for Address Book, Mail and iPhoto.

Deleting files is handled by TM as has been explained already.

Changing a byte in a data base will cause that data base to get backed up on the next TM snapshot. Deleting a byte in a data base will also have the same effect.

It will be wise to exclude the Downloads folder from backups (especially for large downloads that could takes several hours) as TM snapshots will pickup these files (or parts that have been downloaded) multiple times. Plus, typically the downloaded files get moved from the Downloads folder to other places and will subsequently get picked up again by the next TM snapshot.

If Parallels churns data in its virtual volume it will get picked every time by the TM snapshots. It will be the users choice to exclude this from TM snapshots as they wish.

TM is not your regular/traditional backup. It's a compromise between the traditional base+incremental backups and the easy data restoration, system restorations and simplified data restoration for some Applications such as Address Book, iPhoto and Mail along with keeping the amount of data backed up to be useful and of reasonable size. It could be that Apple adds others to be tightly coupled to TM. Third party Apps can also do the same thing with their Apps as Apple has done with their three Apps.

Apple wants to have TM be easy to use by Joe user who quite likely today perform no backups at all. Joe user doesn't want to understand the intricacies of backups. Just plug a 500gig HD in and turn TM on and then forget about it until the time arises to retrieve some lost data, be it a file, photo, contact, Email and even the whole complete system.

It will be of interest to see how this TM feature grows over time.

Stop it!

Time Machine backs up a file. It remains on your designated external drive until you physically remove it.

Delete the file from you computer deliberately, by accident or by foul play and you simply restore the file from the backup when you want to.

Revise the file and on the next backup, Time Machine will attach the change. If the file has been removed from you computer in the meantime, Time Machine does nothing to the backup. There is nothing to see, check or update.

As such, you can literally and purposely, accidently delete and/or fry your drive and use Time Machine to restore you machine to any time in history that has been backed up to your designated external drive.

Think about it. It is called Time Machine. And for a reason.
post #108 of 140
Quote:
Originally Posted by Abster2core View Post

Stop it!

Time Machine backs up a file. It remains on your designated external drive until you physically remove it.

Delete the file from you computer deliberately, by accident or by foul play and you simply restore the file from the backup when you want to.

Revise the file and on the next backup, Time Machine will attach the change. If the file has been removed from you computer in the meantime, Time Machine does nothing to the backup. There is nothing to see, check or update.

As such, you can literally and purposely, accidently delete and/or fry your drive and use Time Machine to restore you machine to any time in history that has been backed up to your designated external drive.

Think about it. It is called Time Machine. And for a reason.

The question is what does it mean to have hourly/daily backups eliminated.

How would that work? Let's assume I spend 8 hours at work working on one file. Through the course of the day my file, work.pages, ends up being TimeMachined into the equivalent of work1.pages, work2.pages...work8.pages (yet they all are named work.pages).

If I go back in time through TimeMachine on an hourly basis, I see each version of work.pages as just work.pages in the finder even though they represent work1.pages, work2.pages, etc.

That makes sense and is a great solution.

Now, however, Apple tells me that it is going to delete the hourly versions once the next day starts. I suppose it could keep 8 versions of this file, but when I TimeMachine back, which one will it present to me?? The latest or all 8 (with copy numbers to display them all in a Finder Window)??

Absent any indication that it is all 8 (and I have seen no evidence of such version numbering), it seems logical to assume that the 1 file it will show for the previous day will be the last one.

Now, what about a File that has been eliminated from the 8th hourly backup, but was around on the 7th hourly backup? When the daily purge occurs would TimeMachine keep the one from the 7th backup, i.e. that TimeMachine rolls up all backups when the purge occurs to keep the latest version of ALL files that it ever backed up during the relevant time frame.

The question I have is when one goes back in Time to this day that has been purged of the hourlies, what do I see and what is available to restore?

1) All files that ever existed on that day with every version of any file that changed.
2) The last version of all files that ever existed on that day?
3) Just the files that existed when the last backup ran before the purge?

Similar issues/questions arise for the weekly and monthly purges.
post #109 of 140
Quote:
Originally Posted by jehrler View Post

The question is what does it mean to have hourly/daily backups eliminated.

1) All files that ever existed on that day with every version of any file that changed.
2) The last version of all files that ever existed on that day?
3) Just the files that existed when the last backup ran before the purge?

Similar issues/questions arise for the weekly and monthly purges.

Yes, I think that's the issue here.
I hope that it might be #2, but #3 is probably more likely.
Then again, as has been said, this should be only matter very infrequently.
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post #110 of 140
Quote:
Originally Posted by jehrler View Post

The question is what does it mean to have hourly/daily backups eliminated.…The question I have is when one goes back in Time to this day that has been purged of the hourlies, what do I see and what is available to restore?

1) All files that ever existed on that day with every version of any file that changed.
2) The last version of all files that ever existed on that day?
3) Just the files that existed when the last backup ran before the purge?

Similar issues/questions arise for the weekly and monthly purges.

First of all, forget or disregard "How Time Machine works"

Best to read Apple's Time Machine info (http://www.apple.com/macosx/leopard/...memachine.html) and view the linked Demo.

I really don't know of a simpler way to describe its functionality.

Just remember that using Time Machine as directed, i.e., attaching an external drive, assigning it to Time Machine and keeping it live and connected everytime you turn on your computer, you'll be able to restore virtually every snapshot of your computer as you create, revise or delete files on your computer.

If you look at the Demo carefully, you'll see Time Machine move from one day to the next at the same time of day, i.e., "6:33 PM." However, if you notice the list of files sorted by "Last Used Date," it appears to be a Spotlight "Result" listing every "Italian Design" file which have been created or altered within minutes of each other and beyond. Are the 'Documents' as listed the same? I don't know. It just seems that Time Machine could be quite granular in its backup process.

Whatever, I feel quite confident that I will be able to back up my entire computer, frag all those files I hesitate to permanently delete and keep my machine lean and mean…and a lot easier and faster than I do now. More important, at anytime, I can travel back in time and restore files that I would normally have to search through hundreds of DAT tapes, CD's or DVDs now.
post #111 of 140
Quote:
Originally Posted by Abster2core View Post

Stop it!

Time Machine backs up a file. It remains on your designated external drive until you physically remove it.

Delete the file from you computer deliberately, by accident or by foul play and you simply restore the file from the backup when you want to.

Revise the file and on the next backup, Time Machine will attach the change. If the file has been removed from you computer in the meantime, Time Machine does nothing to the backup. There is nothing to see, check or update.

As such, you can literally and purposely, accidently delete and/or fry your drive and use Time Machine to restore you machine to any time in history that has been backed up to your designated external drive.

Think about it. It is called Time Machine. And for a reason.

I'm not a developer, but from speaking to those who are, and who have extensively wrung out 10.5 over the time Apple has had it out there, what you are saying is correct.

What I'm seeing here is a lot of speculation about how things are done at various levels in the OS, and I'm wondering if people here really know what they're talking about
post #112 of 140
I don't see what the big deal is here folks.

The OS version every developer has now is the one that will be VERY close to the one released.

Instead of all of this silly arguing back and forth, simply take a look.

Are you all saying that while you are all willing to argue this to death without knowing anything, none of you actually have a TimeMachine drive set up and working?

If not, then nothing said here has been of any value whatsoever.

Someone, set up a drive. All you have to do is to look at what is being saved. This could have been done a month ago. Once you see what is being done, then you will know for certain, and all of this disagreement can end.

Many of the arguments we have here can't easily be proven one way or the other, so they go on for pages. But this one shouldn't even be happening. Either it does what Apple says, or it doesn't. It can be easily found out.

If someone is going to say that it doesn't work yet, so they can't find out, then it's so late in the process it won't be available in the release either.

So, will someone please give correct information from an actual working system?

Thank you.
post #113 of 140
Can you set Time Machine to also back up the Trash? Probably wouldn't make a good default, but there's now technical reason why it couldn't. That would alleviate a lot of these concerns, I'm thinking.
post #114 of 140
Quote:
Originally Posted by melgross View Post

What I'm seeing here is a lot of speculation about how things are done at various levels in the OS, and I'm wondering if people here really know what they're talking about

Actually, what you're seeing is people here looking at all the information we have on "how it works", in contrast to the marketing description, and then asking about a hole that seems to be there in a reasonably unique situation.

For almost any regular users usage, it will work "as advertised".

[edit: The actual article says the deletion "maintains a complete, extensive set of backups that balance out the demands for backup frequency versus disk space."]

On a related note and as I said before, deleting files because they're in the backup is a bad idea - create an archive instead. It's similar to users who store their read emails in the trash because it's convenient.

Quote:
Someone, set up a drive. All you have to do is to look at what is being saved. This could have been done a month ago. Once you see what is being done, then you will know for certain, and all of this disagreement can end.

Good idea!

Could someone with Leopard:
1) create File1 at noon, and delete it 1.5hrs later. Check it's in Time Machine.
2) Create File2 at 2pm, and delete it 1.5 hrs later. Check its in Time machine.
3) Wait till the hourly backups are deleted (2 days later, to be safe?)
4) see if both File1 and File2 are in the daily backup....
post #115 of 140
Quote:
Originally Posted by melgross View Post

I don't see what the big deal is here folks.

The OS version every developer has now is the one that will be VERY close to the one released.

Instead of all of this silly arguing back and forth, simply take a look.

Are you all saying that while you are all willing to argue this to death without knowing anything, none of you actually have a TimeMachine drive set up and working?

If not, then nothing said here has been of any value whatsoever.

Someone, set up a drive. All you have to do is to look at what is being saved. This could have been done a month ago. Once you see what is being done, then you will know for certain, and all of this disagreement can end.

Many of the arguments we have here can't easily be proven one way or the other, so they go on for pages. But this one shouldn't even be happening. Either it does what Apple says, or it doesn't. It can be easily found out.

If someone is going to say that it doesn't work yet, so they can't find out, then it's so late in the process it won't be available in the release either.

So, will someone please give correct information from an actual working system?

Thank you.

I'd love to post some definitive statements for you but cannot until Leo becomes GA. Sorry. I can say I've been testing TM for Apple for the past 12 months. Just be aware that the fine print on Apple's TM web pages state they reserve the right to change things. All your enquiries have merit IMO, as do others. Shouldn't be long now before much of what is being asked about here can be responded with definitive and correct answers.
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post #116 of 140
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post #117 of 140
Excellent article! I really like the explanation of how it's implemented. It seems quite straight forward to me... I dislike the cosmic-looking background in the Time Machine UI. IMHO it looks a little tacky.

Also, I hope Apple does finally introduce ZFS so a changed file doesn't mean a whole new copy of the file taking up hard disc space. Actually, just thinking about it, I wonder if the whole new version of that file does need to be copied to the backup disc. Surely just the differences between the modified file and the older backup file need to be backed up. Would this functionality really need ZFS to work? RSync kind of works in this manner, doesn't it?
post #118 of 140
Quote:
Originally Posted by GregAlexander View Post

Actually, what you're seeing is people here looking at all the information we have on "how it works", in contrast to the marketing description, and then asking about a hole that seems to be there in a reasonably unique situation.

For almost any regular users usage, it will work "as advertised".

[edit: The actual article says the deletion "maintains a complete, extensive set of backups that balance out the demands for backup frequency versus disk space."]

On a related note and as I said before, deleting files because they're in the backup is a bad idea - create an archive instead. It's similar to users who store their read emails in the trash because it's convenient.



Good idea!

Could someone with Leopard:
1) create File1 at noon, and delete it 1.5hrs later. Check it's in Time Machine.
2) Create File2 at 2pm, and delete it 1.5 hrs later. Check its in Time machine.
3) Wait till the hourly backups are deleted (2 days later, to be safe?)
4) see if both File1 and File2 are in the daily backup....

I concur, this is a great idea. In fact, by posing my questions above I was hoping that someone, unlike me, who has access to a nearly GM version would be able to offer insight.

It is not that I am complaining or bitching, I am just trying to discover what, exactly, are the capabilities and limitations of TM. The article offer much new information but seemed to leave these questions open.
post #119 of 140
Quote:
Originally Posted by Abster2core View Post

First of all, forget or disregard "How Time Machine works"

Best to read Apple's Time Machine info (http://www.apple.com/macosx/leopard/...memachine.html) and view the linked Demo.

I really don't know of a simpler way to describe its functionality.

Just remember that using Time Machine as directed, i.e., attaching an external drive, assigning it to Time Machine and keeping it live and connected everytime you turn on your computer, you'll be able to restore virtually every snapshot of your computer as you create, revise or delete files on your computer.

If you look at the Demo carefully, you'll see Time Machine move from one day to the next at the same time of day, i.e., "6:33 PM." However, if you notice the list of files sorted by "Last Used Date," it appears to be a Spotlight "Result" listing every "Italian Design" file which have been created or altered within minutes of each other and beyond. Are the 'Documents' as listed the same? I don't know. It just seems that Time Machine could be quite granular in its backup process.

Whatever, I feel quite confident that I will be able to back up my entire computer, frag all those files I hesitate to permanently delete and keep my machine lean and meanand a lot easier and faster than I do now. More important, at anytime, I can travel back in time and restore files that I would normally have to search through hundreds of DAT tapes, CD's or DVDs now.

I took a look at this Demo and it appears to me that you get in that section where you see the "Italian Design" file is the *one* keynote file and a bunch of documents, each of those with different time stamps. Note that they are not listed as keynote files, just documents.

It seem pretty evident that you get, after the Daily rollup of hourly versions, a single version of the file on the 6:33 snapshot which is, most assuredly, the last one. And, as I mentioned above, how could Apple provide an interface to display all hourly versions of a file when the daily snapshot has only one instance, i.e. the 6:33 rollup??? They would need version numbers and/or date stamps to help the user identify which one to restore.

With no evidence of versioning, it looks like the result is option 2 or 3 in my post earlier.

That leaves the real question of do the rollups (either daily or monthly) keep only the latest version of only those files that STILL exist in the last snapshot before the rollup (option 2) or do they keep the latest version of all files that ever existed in any snapshot in the rollup (option 3).

This is an important difference because, both via children and my own absent mindedness, I have deleted files that I wish I could have gotten back and this is a feature specifically touted.
post #120 of 140
great article.

slightly depressed that it sounds like i cannot have TM backup to my NAS which is connected to all the macs in my studio via AFP. now that would be cool!
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