Time Machine & hardware changes

[-hh]

Had a SMART alert show up yesterday that one of my drives has hit its limit for reallocated sectors, so its time to replace the hardware before it fails.

New drives should arrive via FedEx today; I'll do a clone and swap.

Now here's the question: how dumb/smart is Time Machine?

What I want TM to do is to accept the newly cloned drive as functionally just a continuation of the prior hardware, so rather than to say "Oh, new drive!" and make a complete backup to just continue to make incremental backups.

Reason for this preference is because of the amount of data isn't small: it a working data repository containing a couple of TB's.

Thoughts? Suggestions?


-hh

 

[chabig]

Found this at http://macs.about.com/od/backupsarc...d-Time-Machine-Backup-To-A-New-Hard-Drive.htm

Preparing Your Current Time Machine Drive to be Cloned

- Launch System Preferences by clicking the System Preferences icon in the Dock, or selecting System Preferences from the Apple menu.
- Select the Time Machine preference pane.
-Slide the Time Machine switch to Off.
-Return to the Finder and right-click your current Time Machine hard drive's icon.
-From the pop-up menu, select Eject "Drive Name," where Drive Name is the name of your current Time Machine hard drive.
-Reboot your Mac.
-When your Mac restarts, your current Time Machine hard drive will mount as usual, but your Mac will no longer consider it to be a Time Machine drive. This will allow the Time Machine hard drive to be successfully cloned in the next steps.

Clone Your Time Machine Backup to a New Hard Drive

-Launch Disk Utility, located at /applications/utilities/.
-Select the drive you're currently using for Time Machine backups.
-Click the Restore tab.
-Click and drag the Time Machine volume to the Source field.
-Click and drag the new hard drive volume that you will be using for the new Time Machine drive to the Destination field.
-Select Erase Destination.
WARNING: The next step will fully erase any data on the destination volume.
-Click the Restore button.
-The cloning process will start. This can take a while, depending on the size of your current Time Machine backup.
-During the process of cloning, the destination disk will be unmounted from the desktop, and then remounted. The destination disk will have the same name as the startup disk, because Disk Utility created an exact copy of the source disk, down to its name. Once the backup process is complete, you can rename the destination disk.

Selecting the New Hard Drive for Time Machine's Use

-Once the copying is complete, return to the Time Machine preference pane and click the Select Disk button.
-Select the new hard disk from the list and click the Use for Backup button.
-Time Machine will turn back on.
-That's all there is to it. You're ready to continue using Time Machine on your new, spacious hard drive, and you didn't lose any of the Time Machine data from the old drive.

 

[Weaselboy]

What I want TM to do is to accept the newly cloned drive as functionally just a continuation of the prior hardware, so rather than to say "Oh, new drive!" and make a complete backup to just continue to make incremental backups.

You should get a popup asking if you want to "inherit" the backup. See this article.

 

[-hh]

Found this at http://macs.about.com/od/backupsarchives/qt/Moving-Leopard-Time-Machine-Backup-To-A-New-Hard-Drive.htm

Preparing Your Current Time Machine Drive to be Cloned...

Good to know, but I'm not cloning the TM drive.

What's being replaced (by cloning) is the source drive.

You should get a popup asking if you want to "inherit" the backup. See this article.

Yes, I think this is more of what I'm looking for; looks like the proper terminology is "inherit /re-use".

As a gut check, is there any particular reason why I shouldn't do an inherit?

For example, I could wipe one of my TM backups and start a fresh/new TM backup schema...but I suspect that this might not be a great idea though, because Disk Utility is claiming that the still-operating disk is fatally "bad": there might already have some corrupted files somewhere on the drive that will be faithfully copied over as corrupted onto the cloned copy...if these exist and can be detected & found (how?), I could then in theory go and individually restore them from a pre-corruption copy off of the existing TM backup...but not if the existing TM backup got wiped to make a new TM.

 

[Weaselboy]

As a gut check, is there any particular reason why I shouldn't do an inherit?

I don't see any reason not to just keep using the same backup set. Like you said, it would allow you to potentially go back in time to good versions of corrupted files if any exist.