Time Machine Failure (log provided)

[dmetzcher]

Originally Posted by Doctor X

. . . anyways, do you NEED to save the data on the TM drive? If you already have the data, what you propose may be the easiest thing.

Otherwise, I would consider a better disk repair program such as Disk Warrior. With that one in particular you can take a "picture" of your drive and try to pull files if it does not repair it.

--J.D.

I don't really need anything off the Time Machine disk since it's just a backup of my startup disk. Of course, the hours I'll need to spend waiting for TM to do its thing after I erase the disk is going to be irritating, but stuff happens. My main question is whether or not I should erase the TM disk and tell TM to use it again, or if the disk is physically damaged and I should just scrap it altogether.

I've erased the disk. I ran a disk repair on the erased disk (there's nothing on it right now, so I'd expect to see what I did see, posted below).

Verify and Repair volume “Time Machine”
Checking Journaled HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Checking multi-linked files.
Checking Catalog hierarchy.
Checking Extended Attributes file.
Checking volume bitmap.
Checking volume information.
The volume Time Machine appears to be OK.

Now I'm going to tell TM to use the disk again.

Assuming there is no physical issue with the disk...why did this happen? What have I been seeing here...is this just corruption that sometimes happens? Am I likely to see it again, or is it just bad luck?

I really should invest in DiskWarrior or [another more robust disk utility], but is Mac OS X able to tell me if there are physical issues with the disk itself, or do I have to buy a specialized utility for that?

Thanks.

[Doctor X]

Hrrrrrrm . . . to my knowledge--and I immediately defer to Gurus--Disk Utility does not do a surface scan of the HD to check for/isolate bad blocks. It may. It may do it as part of that snazzy hardware check that takes a night to run. I have never done it.

I am assuming your HD has "SMART" ability? This should, hopefully, tell you if you are having problems with your HD. Of course . . . I have not had an HD failure on a disk that IS "SMART," so take that with a big scoop of salt.

Disk Warrior is a good investment in my opinion of "finding" data. However, since you DO back up disks it may not be as critical. TechTools is good at fixing things AND can do a surface scan on your HD.

Do you need either of those? I defer to the Gurus, but in my limited experience failing HDs, they fail. They may "cough" or "burb" a bit, but then they go. All of the HDs that have died on my--internal HDs of various Powerbooks--DIED.

Save one. Coincidentally, a student told me he had spent the night after a HD failure on a PC. I let him hit me as I asked that annoying question: "Did you back up your data?"

That night, something that ran in the background crashed--on OS 9. As I pulled out my diagnosis disks . . . I thought . . . okay . . . grabbed a bunch of CDs and spent an hour burning critical stuff.

Then I tried to fix . . . DOOM! Now I cannot boot off the drive.

Now, DiskWarrior was able to "take a picture" of the drive, so I could still pull data off if I needed.

I happen to have both since I could get them paid for . Do you NEED such both of such utilities? In my uneducated opinion, DW will fix volumes and find data during a disaster. For fixing permissions and the like, I trust the free Onyx--which is faster--or Cocktail--which is shareware. It does not seem to do as good of a job repairing files like TT.

TT can check things on your computer. You can also make a small "bootable" partition. Critics scoff at this, but that has saved my ass when I have done something really stupid. Its diagnostics are not full-proof with failing RAM. It seems to "upgrade" volumes as well as DW. It can also defrag your HD which, as a thread HERE discusses, may really not be all that bloody necessary in 10.4-10.5+

But . . . it cannot take a "picture" of your HD.

Hope that helps. More to your question: if you have your data backed up, the WORSE that can happen is you discover your drive IS dying and it . . . dies. Then you got to replace it.

--J.D.

[dmetzcher]

Thanks for the info, Doctor X. I'll consider investing in one of the tools. I've been putting it off, but I may find it useful if I have an issue in the future.

I'm getting a weird error now that I'm trying to back up my drive with Time Machine.
Time Machine Saying Not Enough Space on Disk

TM is saying it doesn't have enough room, but it's also saying that it needs more room than it actually needs.

[dmetzcher]

I have a feeling that the fact that the TM backup disk is the same size as the startup volume caused this issue. I cannot get a backup going now (see me most recent previous post), and I just found this:
http://discussions.apple.com/thread....25887&tstart=0

Others have had the same issue. If the TM disk gets too close to full, it sometimes stops backing up. Also, the initial backup requires quite a bit more space than the drive being backed up in order to even get it going.

So I'm stuck now.

I have two internal 500 GB drives. Can I raid them together and use them as a TM disk for the my 500GB startup disk?

[dmetzcher]

A tribute to Mac OS X is the fact that I've never used RAID before and was able, in a few minutes, to set up a striped RAID (0) drive using two internal 500 GB drives, tell Time Machine to use the combined 1 TB drive for the backup volume, and get Time Machine backing up my startup volume.

Not to bash any other operating systems, but I'm not sure how easy this would have been if I were not using a Mac. Easy is the name of the game. It saves me time, frustration, and worry. It also saves those around me from the ranting that would occur if RAIDing weren't easier on a Mac.

I still think that requiring twice the size of the volume being backed up is a little overkill on Apple's part, but I've had this other internal drive sitting around as a Tiger clone since about a year ago when I upgraded to Leopard. I guess I can safely say that I won't be needing it any longer.

So, we'll see how it goes with my new RAID volume.