[mackandproud]

I've always used CCC to backup my internal hard drive.

Questions:

1. can I set up CCC to automatically backup my internal drive at specific intervals, i.e., at the end of the day?

2. Does Time Machine require more space than my original hard drive? For ex. does a 500 GB internal drive require more space for a backup drive?

[mduell]

Cloning is sort of a degenerate backup system; there's no history to it.

Time Machine only needs as much space as is used on the internal drive. Any other space is used to hold multiple revisions of old files.

[mackandproud]

OK, I've got a 500 GB internal and a 2 TB external with a 500 GB partition set aside for Time Machine or CCC. No fudging with partition size, I can go straight ahead and use TM for backups?

Also, I set up the 2 TB with GUID partition and each partition with mac os x extended journal.

Am I good to go with backups?

[mduell]

Yes. x2

It's not ideal for Time Machine, but it will give you at least a single generation of copies (the best that CCC could give you).

[Spheric Harlot]

Originally Posted by mduell 

Cloning is sort of a degenerate backup system; there's no history to it.

Time Machine only needs as much space as is used on the internal drive. Any other space is used to hold multiple revisions of old files.

Technically less, actually, since TM does not back up anything that is included on the original system install disks.

[turtle777]

Originally Posted by Spheric Harlot 

Technically less, actually, since TM does not back up anything that is included on the original system install disks.

Are you sure ?

AFAIK, you can do a complete re-install of a borked OS X from TM, with no need of an install disk.

Am I wrong ?

-t

[cgc]

Originally Posted by turtle777 

Are you sure ?

AFAIK, you can do a complete re-install of a borked OS X from TM, with no need of an install disk.

Am I wrong ?

-t

I think as a minimum you'd have to reinstall from the OSX system discs then restore your stuff from Time Machine. Not sure what the default settings are but I don't backup apps, the system folder, and a few others.

[Doc HM]

Originally Posted by turtle777 

Are you sure ?

AFAIK, you can do a complete re-install of a borked OS X from TM, with no need of an install disk.

Am I wrong ?

-t

Yes you're wrong. Time Machine backups are not bootable. As a minimum you have to install OSX from your original disks. You can backup your system files etc but there's little point since you'll have to reinstall. I exclude all system files form my TM backups. The only use would be to recover old library/ settings files etc.

CCC backups are bootable. A nightly clone of your system drive via CCC can help get you back up and running faster than a TM backup, but you won't get any history.

[jmiddel]

Which is exactly why I invested in SuperDuper, every night it reproduces my internal HD on external ones, which means that I can pretty much sart off running if the internal gets borked.

[P]

Originally Posted by Spheric Harlot 

Technically less, actually, since TM does not back up anything that is included on the original system install disks.

Mine has a backup of the entire system although not marked as bootable. If you add /System to the excluded items, it's smart enough to also exclude stuff like /usr and similar that is also part of the default install, but the default setting (at least on mine) was to include everything.

I think that default may have changed with some OS revision, though.

[OreoCookie]

I would strongly recommend Time Machine instead of Carbon Copy Cloner (or SuperDuper). Cloning your harddrive is a very, very bad backup strategy. Time Machine retains several different time points to which you can restore and a human error + backup won't destroy your ability to restore a file.

Plus, Time Machine is easy to setup, literally fire & forget -- until you need it!

[mackandproud]

I've done a bit more research on TM, and right now, it's cons are outweighing it's pros.

1. it's not bootable.
2. it requires 50% more space than the original drive
3. I doubt I need hourly backups.
4. I need to have the backup drive plugged in/turned on all the time.

I just don't want to lose 250 Gigs, which is the main reason I am eschewing from using TM.

It does have a lovely graphic when 'entering time machine' however.

[OreoCookie]

Originally Posted by mackandproud 

1. it's not bootable.

True, but you should never, ever, ever work off a backup. That's another bad practice which is perpetuated when people use clones.

Originally Posted by mackandproud 

2. it requires 50% more space than the original drive

That's false. Although your backup drive should be quite a bit larger than the data you want to backup so that you can retain as many backups as possible, it doesn't have to be larger than the drive.

Originally Posted by mackandproud 

3. I doubt I need hourly backups.

They're done automatically for free and also removed again. I don't see why this is a con. Time Machine is actually quite smart in this respect: if you catch a mistake (e. g. accidentally saving over a file), you lose at most one hour of work.

Originally Posted by mackandproud 

4. I need to have the backup drive plugged in/turned on all the time.

This is false. If the backup volume is ejected, backups are obviously suspended. Once you reconnect the drive, they'll resume. I do it all the time with my MacBook Pro: the Time Machine drive is at work, I have another backup drive at home (I use Synk for incremental backups).

[turtle777]

It seems you first need to get utterly screwed before you understand that cloning is a bad backup strategy. All for saving a few GB of HD space ?

-t

[Spheric Harlot]

Originally Posted by turtle777 

Are you sure ?

AFAIK, you can do a complete re-install of a borked OS X from TM, with no need of an install disk.

How?

[OreoCookie]

People used to do clones, because it was an easy-to-understand, easy-to-setup way to do backups. They had the same shortcomings they have now, but at least it was some form of backup. With Time Machine, there is no reason to rely solely on clones. Perhaps it may make sense for some people to clone their drives in addition to incremental backups (e. g. via Time Machine), but not the other way around.

Also, I wouldn't use disk space as an excuse. Disk space these days is very cheap, you can easily get 2 TB drives for ~€80 and 1.5 TB drives for €65. (Even though the OP probably doesn't even need a larger backup drive.)

[mackandproud]

I went with TM.

The thing that dissuaded me from CCC is that I have to manually back up specific files every time. Whereas TM does this for me. It is more convenient, although it's not bootable.

Some of the other cons have been addressed. What I meant to say is that my 500 GB original drive is nearly full, so practically speaking I do need 50% more space than the original drive.

Yes, gigs are relatively cheap, but who wants to give up 250 Gigs for any reason.

I wonder if Apple can create a bootable TM next time.

[OreoCookie]

Originally Posted by mackandproud 

Some of the other cons have been addressed. What I meant to say is that my 500 GB original drive is nearly full, so practically speaking I do need 50% more space than the original drive.

If your 500 GB drive is nearly full (~85 % or more), you should replace it in either case. 2 TB drives are cheap and this will give you a noticeable performance boost. Plus, OS X starts acting funny if you have less than 10, 15 GB of disk space available.

Originally Posted by mackandproud 

Yes, gigs are relatively cheap, but who wants to give up 250 Gigs for any reason.

You don't give up disk space, you invest it for a specific purpose. Investing it into a proper backup solution is an absolute necessity, not a luxury.

[OreoCookie]

Originally Posted by Spheric Harlot 

How?

Well, you do need an install DVD to boot. But then you can restore a system from a Time Machine drive without having to install OS X. To my knowledge, all it does is transfer the files from the backup volume to the volume you restore to.

[AKcrab]

Originally Posted by OreoCookie 

Well, you do need an install DVD to boot. But then you can restore a system from a Time Machine drive without having to install OS X. To my knowledge, all it does is transfer the files from the backup volume to the volume you restore to.

This is correct.

[mackandproud]

What's the max capacity for a laptop hard drive these days? 750?

Right now, I have a 7200 rpm 500 gb from hitachi.

To be honest, it's not that reliable. Maybe because I constantly run it with so little free hard drive space?

If I move up, I would want to stay at 7200 rpm. Are there 750 gb hard drives available at that speed?



edit: it looks like seagate sells a 750 gb 7200 rpm drive, for just over $100. That's pretty impressive.

I would prefer 1 TB, but I'm assuming that would take at least 6 months to come to market.

[finboy]

Originally Posted by jmiddel 

Which is exactly why I invested in SuperDuper, every night it reproduces my internal HD on external ones, which means that I can pretty much sart off running if the internal gets borked.

Same here. Only way to fly in OS X.

[finboy]

Originally Posted by OreoCookie 

Cloning your harddrive is a very, very bad backup strategy.

Especially if you're trying to maximize the hassle of getting restored and back to productivity. NEVER clone your drive as a backup unless you're just DYING to actually Get Real Work Done(TM).

[mackandproud]

You guys suck. Such good arguments for both.

Maybe I'll set up TM AND CCC!

[CharlesS]

Originally Posted by Spheric Harlot 

Technically less, actually, since TM does not back up anything that is included on the original system install disks.

Huh? It backs up almost everything that's installed by the install discs. The things it skips are mostly things like caches and logs which are automatically generated, and thus not installed by the install discs.

Originally Posted by finboy 

Especially if you're trying to maximize the hassle of getting restored and back to productivity. NEVER clone your drive as a backup unless you're just DYING to actually Get Real Work Done(TM).

Because opening Migration Assistant and clicking "Continue" a few times is just so hard.

[Spheric Harlot]

Originally Posted by CharlesS 

Huh? It backs up almost everything that's installed by the install discs. The things it skips are mostly things like caches and logs which are automatically generated, and thus not installed by the install discs.

Yeah, I got it.

I stand corrected.

Originally Posted by CharlesS 

Because opening Migration Assistant and clicking "Continue" a few times is just so hard.

I would never rely on a single clone and use that for work if the main drive crashed.

But keeping a working clone IN ADDITION to either a second clone or a TM backup makes a lot of sense in some situations:

Using the Migration Assistant isn't "hard", but it generally takes an hour or more. That can be completely unacceptable, depending upon the job.

[OreoCookie]

Originally Posted by finboy 

Especially if you're trying to maximize the hassle of getting restored and back to productivity. NEVER clone your drive as a backup unless you're just DYING to actually Get Real Work Done(TM).

Restoring from a Time Machine backup and from a clone to a new harddrive takes the same amount of time.

Besides, you should have written `never clone a dying harddrive to actually get work done.'

[OreoCookie]

Originally Posted by Spheric Harlot 

But keeping a working clone IN ADDITION to either a second clone or a TM backup makes a lot of sense in some situations:

In addition in certain situations? Yes. As a substitute? Nope. So that you can boot off your backup and work off it? Nope. You don't work off backups.

Originally Posted by Spheric Harlot 

Using the Migration Assistant isn't "hard", but it generally takes an hour or more. That can be completely unacceptable, depending upon the job.

Why is MA supposedly slower? In both cases, you're limited by the throughput of the harddrive. If you connect via USB or FireWire, the interface is the limiting factor here -- and that's independent of the actual recovery method.

[Spheric Harlot]

I meant Migration Assistant as a term for anything restoring from a TM backup.

And that takes time.

If your stage machine conks out a half-hour before the show, you swap in a cloned drive and boot that ****er. If your drive conks out during a studio session and the client is paying everybody present by the hour, you grab a clone and boot that ****er.

Sometimes you just don't have time for troubleshooting/restoring.

Of course that's one of several redundant clones/backups.

[OreoCookie]

Originally Posted by Spheric Harlot 

I meant Migration Assistant as a term for anything restoring from a TM backup.

I agree with your example, but as you note, it's not Time Machine or anything that takes time, but recovery from any sort of backup. In the example that you use (which is real enough), you don't recover from a backup, you use the cloned drive for redundancy (`like a RAID1').

[mduell]

Originally Posted by finboy 

Especially if you're trying to maximize the hassle of getting restored and back to productivity. NEVER clone your drive as a backup unless you're just DYING to actually Get Real Work Done(TM).

Are you trying to use cloning as a poor substitute for mirroring?

[cgc]

This discussion was held a few months ago in a different thread where I was the CCC supporter. I began using TM and haven't looked back. Great program that's allowed me much more flexibility in restores (I tinker a bit and it's nice to be able to restore from a backup that occurred an hour earlier). Wouldn't consider a clone a backup but a clone may be handy as a secondary thing to have to get a system up quickly so you can restore files from TM, though a RAID 1 w/ TM would be ideal (for me).

[mackandproud]

How many backups does TM create anyway? It cannot create a full backup of the entire drive each time or else the backup drive would be out of space very quickly. Right now, I have 6 dated backups. How much is being backed up each time?

[AKcrab]

TM starts with a full backup. It then checks every hour for what has changed and backs that up. Eventually it will fill up a drive and ask you if you want to remove old backups.

[CharlesS]

Originally Posted by mackandproud 

How many backups does TM create anyway? It cannot create a full backup of the entire drive each time or else the backup drive would be out of space very quickly. Right now, I have 6 dated backups. How much is being backed up each time?

Shameless plug:

http://www.charlessoft.com/TimeTracker.zip

[mackandproud]

Let's see if I understand: 1 full backup, then a slew of hourly incremental backups (each of which stores any variation from the original, but not the original).

So, I would have to manually delete the incremental backups in order to save space on the disk?

Right now, I do one or two manual backups a day. I don't really have a need for more backups than that right now.

Originally Posted by AKcrab 

TM starts with a full backup. It then checks every hour for what has changed and backs that up. Eventually it will fill up a drive and ask you if you want to remove old backups.

[P]

Originally Posted by mackandproud 

Let's see if I understand: 1 full backup, then a slew of hourly incremental backups (each of which stores any variation from the original, but not the original).

Yes, pretty much.

Originally Posted by mackandproud 

So, I would have to manually delete the incremental backups in order to save space on the disk?

No, Time Machine does that automatically - it's called "thinning". It keeps hourly backups for the last week or so, then daily backups for a few months, then only weekly backups and so on. The exact parameters are dynamic, I think - meaning that it will make use of the space you give it.

Originally Posted by mackandproud 

Right now, I do one or two manual backups a day. I don't really have a need for more backups than that right now.

You can configure Time Machine to run less often by editing plists, but you really ought to leave it alone. Dedicate a drive (or a partition) to it and let it be. The bigger the drive, the denser the backups it will keep.

[OreoCookie]

Originally Posted by P 

You can configure Time Machine to run less often by editing plists, but you really ought to leave it alone. Dedicate a drive (or a partition) to it and let it be. The bigger the drive, the denser the backups it will keep.

I agree: you shouldn't muck with Time Machine, just switch it on and leave it as it is.

[mduell]

Originally Posted by mackandproud 

How many backups does TM create anyway? It cannot create a full backup of the entire drive each time or else the backup drive would be out of space very quickly. Right now, I have 6 dated backups. How much is being backed up each time?

Originally Posted by mackandproud 

Let's see if I understand: 1 full backup, then a slew of hourly incremental backups (each of which stores any variation from the original, but not the original).

So, I would have to manually delete the incremental backups in order to save space on the disk?

Right now, I do one or two manual backups a day. I don't really have a need for more backups than that right now.

Time Machine makes a full backup every hour. You can open the folder for the latest backup (or any prior backup) and see every file there. But it uses a file system feature called hard links so there's only actually one copy of each unique file contents on the disk. So if 1% of your data changes every hour, you could fit about 500 backups in the place of 6 clones. Time Machine also automatically thins the backups, only keeping the hourlies for a day, the dailies for a month, and weeklies after that until the disk is full.

So if we assume your data changes 0.5% an hour, 2% a day, and 5% a week you get:
24 hourly backups
30 daily backups
80 weekly backups
or a bit over a year and a half in the space of 6 clones.

[CharlesS]

Originally Posted by mackandproud 

Right now, I do one or two manual backups a day. I don't really have a need for more backups than that right now.

That's what I thought at first too, but it turns out to be pretty handy, and on the modern dual-core machines it doesn't seem to affect performance noticeably. Don't knock it until you've tried it.

[mackandproud]

When I back up, only new files are backed up, based on the amount of data being processed. There must be some sort of linking system as you say which prevents this unnecessary redundancy. I'll figure it out eventually.

Originally Posted by mduell 

Time Machine makes a full backup every hour. You can open the folder for the latest backup (or any prior backup) and see every file there. But it uses a file system feature called hard links so there's only actually one copy of each unique file contents on the disk. So if 1% of your data changes every hour, you could fit about 500 backups in the place of 6 clones. Time Machine also automatically thins the backups, only keeping the hourlies for a day, the dailies for a month, and weeklies after that until the disk is full.

So if we assume your data changes 0.5% an hour, 2% a day, and 5% a week you get:
24 hourly backups
30 daily backups
80 weekly backups
or a bit over a year and a half in the space of 6 clones.

[mduell]

It's called a hard link. After the first copy is created on the backup drive each additional backup just increments the reference count. Time Machine creates one for each file on your drive with every backup.

It's a great way to do backups; the rsync utility on most unix-like systems can achieve the same result but it's not nearly as user friendly.

[besson3c]

Originally Posted by CharlesS 

Huh? It backs up almost everything that's installed by the install discs. The things it skips are mostly things like caches and logs which are automatically generated, and thus not installed by the install discs.

Another item worthy of note here... If you rely on data that accumulates outside of your home directory in a usual spot, there is a good chance that TM will miss it. The mail spool on OS X Server is a good example. However, I don't know whether it will catch some random directory you create at the root level of your hard drive, or exactly what non-traditional directories it will overlook. Will it backup the Macports /opt directory? This obviously applies to very few people, but I'd be interested to know which directories it will not backup. Perhaps there are people that have bad habits of not using their home directory for whatever reason.

If there are directories like this, perhaps Apple should periodically the HFS+ journal and try to catch writes to directories not supported by TM when TM is running and alert you to these, offering you the possibility to add this directory to the backup.

[besson3c]

Originally Posted by mduell 

It's called a hard link. After the first copy is created on the backup drive each additional backup just increments the reference count. Time Machine creates one for each file on your drive with every backup.

It's a great way to do backups; the rsync utility on most unix-like systems can achieve the same result but it's not nearly as user friendly.

I think you mean cpio?

[besson3c]

Originally Posted by mackandproud 

Let's see if I understand: 1 full backup, then a slew of hourly incremental backups (each of which stores any variation from the original, but not the original).

So, I would have to manually delete the incremental backups in order to save space on the disk?

Right now, I do one or two manual backups a day. I don't really have a need for more backups than that right now.

If you want to limit how much of the drive is used by backups you can partition it and devote a partition to backups. Time Machine will use as much space as you give it, and will just keep on adding backups until you run out of space on that drive/partition.

Disk Utility will allow you to re-partition an external drive without having to reformat it.

[AKcrab]

AppleInsider | Road to Mac OS X Leopard: Time Machine [Page 1]

Geek out. It's probably more info than anyone wants.

[CharlesS]

Originally Posted by besson3c 

Another item worthy of note here... If you rely on data that accumulates outside of your home directory in a usual spot, there is a good chance that TM will miss it.

Only if it's in a directory that Time Machine is specifically set up to ignore. These are mostly cache and log directories. Most directories that you would actually put stuff in do not fall in this category.

The mail spool on OS X Server is a good example.

On my system, the only directories in /private/var/spool that are getting excluded are cups, uucp, and fax, so unless something's different in Server, that shouldn't be an issue.

However, I don't know whether it will catch some random directory you create at the root level of your hard drive,

It will.

or exactly what non-traditional directories it will overlook.

They're enumerated in /System/Library/CoreServices/backupd.bundle/Contents/Resources/StdExclusions.plist.

Will it backup the Macports /opt directory?

Yes.

This obviously applies to very few people, but I'd be interested to know which directories it will not backup. Perhaps there are people that have bad habits of not using their home directory for whatever reason.

Even if they do, it'll still get backed up, unless they're doing something like storing their critical data in /Library/Caches, or in the Trash.

If there are directories like this, perhaps Apple should periodically the HFS+ journal and try to catch writes to directories not supported by TM when TM is running and alert you to these, offering you the possibility to add this directory to the backup.

That would be extremely annoying, since it would alert you every time the OS saved a cache or a log file.

[besson3c]

Originally Posted by CharlesS 

Only if it's in a directory that Time Machine is specifically set up to ignore. These are mostly cache and log directories. Most directories that you would actually put stuff in do not fall in this category.


On my system, the only directories in /private/var/spool that are getting excluded are cups, uucp, and fax, so unless something's different in Server, that shouldn't be an issue.

Restoring Mac OS X Server from Time Machine � Der Flounder

Mail – On 10.5 Server (I don’t know about 10.6.x Server), Time Machine does not back up the /private/var/spool directory. As a result, nothing in /private/var/spool or the directories inside spool are backed up. This is important for those running a mail server because /private/var/spool/imap which is where IMAP users’ E-mail is stored.

More:

Designed to Fail: Apple Time Machine and MacOS X Server - Bill's Words

E-mail didn’t work. Web services wouldn’t start. All hell was breaking loose in the system logs as various services which were trying to start up just plain wouldn’t start up. Things which previously had a quiet existence on this machine were suddenly vociferously complaining about a plethora of problems. While each had its own gripe, most were unhappy about the nonexistence of a log directory, /var/log. “Huh?” I thought to myself, “I thought I read that Time Machine backed up my entire machine to get it back to its original state. What’d I miss? And why do I feel like it’s my fault all of a sudden?”

A little searching on the web reveals that there’s a list of stuff Time Machine doesn’t back up which, on a normal MacOS client machine might be OK, but for a server is disastrous. The list, stored at

/System/Library/CoreServices/backupd.bundle/Contents/Resources/StdExclusions.plist
has, among other things, these items which are excluded

/private/var/log
and

/private/var/spool

Maybe this was addressed in an OS update, but I figured it was for this reason that Time Machine and Server were not a recommended pairing?

That would be extremely annoying, since it would alert you every time the OS saved a cache or a log file.

I meant other than the obvious exclusions However, it appears that the /private/var/spool directory was a mistake on Apple's part at some point, and that other than this everything else will make the backup, so that renders what I wrote moot.

[CharlesS]

Originally Posted by besson3c 

Restoring Mac OS X Server from Time Machine � Der Flounder

More:

Designed to Fail: Apple Time Machine and MacOS X Server - Bill's Words

Maybe this was addressed in an OS update, but I figured it was for this reason that Time Machine and Server were not a recommended pairing?

Those two links have one thing in common — they are both talking about Mac OS X 10.5. In 10.5, /private/var/spool is in the plist file containing the list of exclusions. In 10.6, it is not (check it yourself to see what is and isn't excluded!).

Again, it's possible that this file could be set up differently in Server, but I doubt it.

I meant other than the obvious exclusions However, it appears that the /private/var/spool directory was a mistake on Apple's part at some point, and that other than this everything else will make the backup, so that renders what I wrote moot.

Yup, most of the directories that are excluded are invisible, and the ones that aren't are generally places you'd never store stuff in.

[besson3c]

Originally Posted by CharlesS 

Those two links have one thing in common — they are both talking about Mac OS X 10.5. In 10.5, /private/var/spool is in the plist file containing the list of exclusions. In 10.6, it is not (check it yourself to see what is and isn't excluded!).

Again, it's possible that this file could be set up differently in Server, but I doubt it.

So, just a major 10.5 blunder I guess... I wonder if this was corrected later in an update? Is TM the official Apple recommended product for OS X Server? The other problem with running TM on Server is that many servers running off of basic SATA drives simply couldn't manage the performance hit having the disks hammered away at every hour, so I wouldn't be surprised if TM was considered more of a client solution by design.

Yup, most of the directories that are excluded are invisible, and the ones that aren't are generally places you'd never store stuff in.

Cool!

I do like TM. What is the status of network backup? That is one thing I've lost track of. I remember way back when 10.5 came out trying to monkey around with getting it to backup to my Ubuntu box by pointing it at an already mounted disk served by either AFP/Netatalk or SSHfs, but I never got this to work properly and grew tired trying to force the issue. It would be wonderful if you could point it at a mount for a network disk and have it figure out how to re-establish that mount as needed.