MacBook HD Failure - worry of carrying over file structure errors?

dick the flick wrote:
. . .
My worry is that having once again installed a new hard drive and re-built everything from a Time Machine back-up, a clever Mac friend suggests that I may be carrying over a FILE STRUCTURE ERROR that exists on the TM back up which could cause the same issue over an over again?

If this is a possibility

Doubtful. Time Machine is a file-level utility, not a block-by-block one. That means your TM drive has it's own file structure.

There is a possibility that as your internal HD was failing, it damaged some thing(s), and that damage was backed-up. In that case you may not be able to restore from the backups, or some items won't be restored or won't be complete.

Your best bet is probably to do a full system restore, per #14 in [Time Machine - Frequently Asked Questions|http://web.me.com/pondini/Time_Machine/FAQ.html] (or use the link in *User Tips* at the top of the +Time Machine+ forum).

If that fails, or has problems, do it again, but choose an earlier backup, from before the problems started.

dick the flick wrote:
If this is a possibility - is there anything I can do that negates my having to re-install everything again from scratch? (including copious authorisations and licenses for a huge amount of software from Quicktime AVID codecs for use with locking movies to my DAW and Music Sample Libraries!)

I actually prefer to reinstall everything every time I get a new hard drive. There is always junk that needs to be cleaned out. I create read/write disk images of all my install disks and then reinstall from those. I add files with my license codes right on the installer. I have a hard drive with a number of partitions that contain installers for various OS versions. It is much easier and faster than using optical media.

Of course, I don't always have the time to do a full reinstall. My wife's hard drive died 2 days ago so I restored her system via Migration Assistant from a rebuilt system.

I think it is unlikely that you would have backed up either file system errors or corrupt data. It is possible to backup misconfigurations and/or flaky 3rd party software, but you are getting hardware errors, so I don't think that is the case.

Since you do have a complicated install, it might be a good idea to create all those disk images and license files and store them on a goodly sized hard drive. Then, rebuild your system and install all of your software. Use a cloning tool like Carbon Copy Cloner to make a snapshot of a clean install of your system with all your software. I don't like to make clones of used and possibly flaky file systems, but a newly constructed system is definitely something worth saving.

Hey Dick,

just to get down and technical, since it feels like you did not understand all the facts (no offense, please, I will try to explain).

When a hard drive fails mechanically or physically, and, let's say, makes the computer crash, there is a pretty good possibility that files that were open at the time of the crash were not saved properly, and thus are broken. It's just a consequence from the failure and the crash, if it happened. It's not DUE to the failure itself.

So, if you have a TM backup, which, as was stated before, is just files copied to some other drive somewhere on the network, there is no way you could reintroduce some physical damage, that was on your internal drive, back to a new one. If you HAD a utility that would do a 1:1 copy of a drive, there would be the possibility that defective blocks would be copied, but not with TimeMachine.

Let's be theoretical.

Let's say your hard drive failed in stages. Let's say you were working on a project. And let's assume you had a bunch of files open, when the drive initially failed. The system crashed, and some of those files were damaged. Let's further assume that you rebooted the system, and did a backup. And let's finally assume that you THEN changed the drive and restored the backup to the new drive.

Now, in THIS particular case, that would mean that there is a possibility that you backed up one or more damaged files to the TM (since a damaged file is still that: A file) and then restored it.

Now let's finally assume that THEN, after the restore, was the first time you tried to open those particular files after the first crash. You would then see that they are broken.

To sum this up: That's the only scenario I can imagine how to get something damaged "back from the grave". Apart from that, it may just be bad luck that your drive failed for the second time, and I am pretty certain that you don't have a defective backup.

I hope I made some things clear. Please let us know if you have any further questions, and don't be afraid if they might sound dumb to you. There's no such thing as a dumb question. Just dumb answers 🙂

i.

Ingo F. wrote:
. . .
Now, in THIS particular case, that would mean that there is a possibility that you backed up one or more damaged files to the TM (since a damaged file is still that: A file) and then restored it.

Now let's finally assume that THEN, after the restore, was the first time you tried to open those particular files after the first crash. You would then see that they are broken.

There is another possible variation or addition; that something in OSX was damaged and backed-up. In that case, if you do a full system restore, there's a chance it may not boot, or may crash more or less immediately. That's why I'd recommend trying a full restore from your most recent backup; but if that doesn't work, try again from an earlier one.

There are alternatives, too, if that fails. Give the full restore a try; if that doesn't work, let us know.

Cool. Follow #14 in [Time Machine - Frequently Asked Questions|http://web.me.com/pondini/Time_Machine/FAQ.html], and you'll most likely be fine.

Keep us posted.

dick the flick wrote:
🙂

Just incase there was an issue with formatting after startup ........ I rebooted and this time the new Drive "Runningwater HD" appears in SELECT A DESTINATION and I'm now restoring (as you suggest) a complete TimeMachine restore ...... will report back!

Isn't that a bit odd - I did everything in correct order as per instructions #14 in Time Machine - Frequently Asked Questions ...... yet the OSX having formatted the disc, didn't then present the formatted new drive in the DESTINATION window?

Odd, indeed.

But glad it seems to be working!

A note: The restore will rename the HD back to the original name. But it's easily changed; right-click it in a Finder window's sidebar for the option to rename it.

dick the flick wrote:
Thanks James ......... the natives are all happy bunnies!

Yay! (Nothing worse than a sad bunny.)

I would have expecting the result to turn up as the Destination disc that the Time Machine would then copy over to (?)..... so I there was a moment where I thought perhaps some part of the SATA hardware had gone down ...... but when I re-booted after formatting the disc - the restore function worked.

That is odd. I wonder if something was cached or marked in some way, so the change wasn't recognized. There's at least one thing in Disk Utility like that -- if you erase a partition, it gets a new UUID, but Disk Utility keeps displaying the old one unless you quit DU and start it again.

Anyway, glad it's sorted out, and thanks for the star.