An open community 
of Macintosh users,
for Macintosh users.

FineTunedMac Dashboard widget now available! Download Here

Previous Thread
Next Thread
Print Thread
Time Machine error: spurious?
#42893 11/28/16 06:06 PM
Joined: Aug 2009
Likes: 7
jchuzi Online OP
OP Online

Joined: Aug 2009
Likes: 7
I use Checkmate 1.1.5 (the latest version) to run daily diagnostics on my hard drives. Lately, it has found consistent volume structure errors which I have repaired with Disk Warrior. This seems to have started after I upgraded from El Capitan to Sierra (both Checkmate and DW have not been updated for Sierra and, supposedly, both are compatible). The last time that I used DW to rebuild the directory, the following summary appeared (I'm not going to post the details because it is too many pages):

DiskWarrior has successfully built a new optimized directory for the disk named "Time Machine." The new directory is ready to replace the original directory.

There is not enough contiguous free space for a fail-safe replacement of the directory. It is highly recommended that you create 14714 MB of contiguous free space before replacing the original directory.

All file and folder data was easily located.

Optimizing the Catalog Tree Directory File has increased available disk space.
Optimizing the Attributes Tree Directory File has increased available disk space.

Comparison of the original and replacement directories indicates that there will be changes to the number, the contents and/or the attributes of the files and folders. It is recommended that you preview the replacement directory and examine the items listed below. All files and folders were compared and a total of 336,298,680 comparison tests were performed.

• Errors, if any, in the directory structure such as tree depth, header node, map nodes, node size, node counts, node links, indexes and more have been repaired.

• 122 Files had a directory entry with an incorrect text encoding value that was repaired.

• 15 Folders had a directory entry with an incorrect custom icon flag that was repaired.

• 2 Folders had a directory entry with an incorrect text encoding value that was repaired.

• Incorrect values in the Volume Information were repaired.


Disk Information:

Files: 14,001,475
Folders: 2,554,643
Free Space: 14.65 GB
Format: Mac OS Extended (Journaled) Block Size: 4,096
Disk Sectors: 3,906,357,344 Media: Hitachi HUA722020ALA330

Time: 11/19/16, 10:42 AM
DiskWarrior Version: 5.0


Today, CM again reported volume information errors but I decided to try Disk Utility. DU found nothing to repair. I did not run DW.

Is CM giving spurious information? Any thoughts?


Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
Re: Time Machine error: spurious?
jchuzi #42899 11/28/16 07:37 PM
Joined: Aug 2009
Offline

Joined: Aug 2009
Quote:
There is not enough contiguous free space for a fail-safe replacement of the directory.

ANYTIME I get that message I do the same thing. Cancel the rebuild. Re-run it. (because you can't click "preview" at that point), THEN click Preview. Attach backup storage. Make a complete clone from the preview. iirc you have to cancel again and rerun again because Replace is no longer an option. Then replace. Takes a LOT longer to do all of that, but on rare occasion it's totally worth it.

Of the hundreds of times I've done that, FIVE times the repair has aborted midway though, leaving the drive trashed beyond recognition and requiring me to reformat and restore from the backup I just made. Once before this was my golden rule, it trashed it and I had no way to repair it, it was toast. DW wouldn't find any changes to make when reran.

So, odds are really low that it will blow up, but IMHO it's just not worth it. Even with long odds, the losses are just too high to risk.

DW's Preview option is absolutely their best feature. Treasure it!


BTW, don't do like they say and "make free space". No. Do NOT write to a drive with a damaged directory. That's just asking for trouble.


I work for the Department of Redundancy Department
Re: Time Machine error: spurious?
Virtual1 #42901 11/28/16 07:51 PM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
I'm glad this came up, because for ages I've been meaning to ask you how you clone from DW's Preview window?

Thanks.


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
Virtual1 #42905 11/28/16 09:12 PM
Joined: Aug 2009
Likes: 7
jchuzi Online OP
OP Online

Joined: Aug 2009
Likes: 7
AFIK, TM is working. I just tested it by restoring from the a file that had not been altered (so nothing had changed). Do you advise reformatting and creating a TM backup from scratch? That's the only other option that I can see.


Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
Re: Time Machine error: spurious?
artie505 #42923 11/29/16 01:21 PM
Joined: Aug 2009
Offline

Joined: Aug 2009
Originally Posted By: artie505
I'm glad this came up, because for ages I've been meaning to ask you how you clone from DW's Preview window?

NP. When you click "Preview" it should mount the "proposed repaired disk" on the desktop. If the original volume was mountable, it also will be mounted, allowing you to compare them. If you clone, be sure you are cloning from the preview, not the original. I always compared the sizes of the two, to make sure "nothing catastrophic" was being proposed. And about 2% of the time, it WAS. Like used disk space going from 87gb to 13gb following the "repair". NOPE NOPE NOPE not gonna do it! In that case, try another tool or clone from original, nuke, and restore. I had to learn that lesson the hard way too. Note that once you click Repair, there's no undo. You can't just rerun DW and give it another try either.


I work for the Department of Redundancy Department
Re: Time Machine error: spurious?
jchuzi #42924 11/29/16 01:27 PM
Joined: Aug 2009
Offline

Joined: Aug 2009
Originally Posted By: jchuzi
AFIK, TM is working. I just tested it by restoring from the a file that had not been altered (so nothing had changed). Do you advise reformatting and creating a TM backup from scratch? That's the only other option that I can see.

Honestly, I've dealt with a few dozen time machine backup drives that were having issues, and the best thing I can suggest is nuke it and start over. Those volumes just weren't intended to be repaired, there's a metric crapton of hard links on them and it just overruns any tool you try to use on them. When it comes time to retire a TM drive for whatever reason, I usually just unplug it and stick it on the shelf and get another one. Storage is cheap, and that way I have an old archival backup in the unlikely event I need to dig up something really old. That's what I'd suggest you do, shelve the drive that's giving you issues, and start over. Your new drive will be faster, bigger, younger, and known good, plus you'll have that archival backup in the closet (or offsite, even better!) in case you need it.

(a thunderbolt SSD TM drive for your mac with the SSD in it... is a beautiful thing)


I work for the Department of Redundancy Department
Re: Time Machine error: spurious?
Virtual1 #42929 11/29/16 03:03 PM
Joined: Aug 2009
Likes: 7
jchuzi Online OP
OP Online

Joined: Aug 2009
Likes: 7
I nuked the TM drive this morning and created a new one, just as you suggested. Checkmate runs all kinds of tests on the drive (including surface scans, etc.) so I assume that the physical drive is OK. Sooner or later (hopefully sooner), I'll replace the drive with an SSD. For now, at least, all seems to be well. And yes, the drive is in a Thunderbolt enclosure.

For the record, one of the reasons why I nuked it was that, when I tried an experimental restore, I got the spinning beachball for several seconds before anything happened.


Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
Re: Time Machine error: spurious?
Virtual1 #42930 11/29/16 03:30 PM
Joined: Aug 2009
Likes: 16
Moderator
Offline
Moderator

Joined: Aug 2009
Likes: 16
Originally Posted By: Virtual1
(a thunderbolt SSD TM drive for your mac with the SSD in it... is a beautiful thing)

Even more beautiful to me is a Thunderbolt RAID 5 array with SSD drives. The same Thunderbolt Raid 5 array with spinning rust drives is also a very attractive proposition, a lot less expensive and still pleasingly fast. That is what I use for my Time Machine drive and should one of the drives in the array fail, I can hot swap a new drive and the system will recreate the contents of the failed drive automatically. (I haven't tested that in a Time Machine backup set, but in theory it should work.)

However, as V1 points out there is a "metric crapton of hard links" in a Time Machine data set so in all likelihood even though the failed drive could be recreated automatically, I would probably scrub the array and start over with a new data set. My belt and suspenders backup solution is therefore to specify two Time Machine drives; the Thunderbolt RAID 5 array and a Time Capsule. Time Machine automatically alternates backups between the two so if either one fails I still have a backup data set that is at most two hours out of date. That way I have little or no hesitation scrubbing a failed data set and creating a new one. I have restored individual files and even performed a full system restoration from this setup and the only indication which data set Time Machine chooses is the speed of the restore/rebuild. Obviously the Thunderbolt RAID 5 array is orders of magnitude faster.


If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein
Re: Time Machine error: spurious?
Virtual1 #42941 11/30/16 12:36 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Virtual1
Originally Posted By: artie505
I'm glad this came up, because for ages I've been meaning to ask you how you clone from DW's Preview window?

NP. When you click "Preview" it should mount the "proposed repaired disk" on the desktop. If the original volume was mountable, it also will be mounted, allowing you to compare them. If you clone, be sure you are cloning from the preview, not the original.

Thanks, but I'm still not sure how to go about creating the actual clone.

Does Carbon Copy Cloner see the Preview, for instance?


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #42946 11/30/16 12:53 PM
Joined: Aug 2009
Offline

Joined: Aug 2009
Originally Posted By: artie505
Thanks, but I'm still not sure how to go about creating the actual clone.

Does Carbon Copy Cloner see the Preview, for instance?

Most tools will see DW's preview. When it's in preview mode, it has mounted up the original volume as read-only, (if possible) and then creates a second virtual volume, a bit like a disk image, using it's rebuilt directory structure to point to the files on the original volume, also mounted read-only. So any tool that can work on virtual volumes (disk images), which most can, should be fine with that. Just so long as it doesn't try to unmount the volume (or write to it) during the copy/scan/whatever. DW freaks out a bit if one or both volumes are unmounted while being previewed. The two volumes will look very similar, so make sure you clone the correct volume.


I work for the Department of Redundancy Department
Re: Time Machine error: spurious?
Virtual1 #42976 12/01/16 08:42 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Got it! Thanks.

It'd be nice if I had DW to play with. (Hmmm... I wonder if running an older version will be dangerous if I don't go past Preview? Naaah, not even worth trying.)


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #42979 12/01/16 02:24 PM
Joined: Aug 2009
Offline

Joined: Aug 2009
Originally Posted By: artie505
It'd be nice if I had DW to play with. (Hmmm... I wonder if running an older version will be dangerous if I don't go past Preview? Naaah, not even worth trying.)

DW is a bit OCD on that, it won't run on a disk that it can tell was used by an OS that's beyond the version it supports.


I work for the Department of Redundancy Department
Re: Time Machine error: spurious?
Virtual1 #42981 12/01/16 02:36 PM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Virtual1
Originally Posted By: artie505
It'd be nice if I had DW to play with. (Hmmm... I wonder if running an older version will be dangerous if I don't go past Preview? Naaah, not even worth trying.)

DW is a bit OCD on that, it won't run on a disk that it can tell was used by an OS that's beyond the version it supports.

And yet a while back a poster reported running DW v 4.x on a version of OS X that, per Alsoft, was not supported.


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #42984 12/01/16 05:51 PM
Joined: Aug 2009
Likes: 8
Offline

Joined: Aug 2009
Likes: 8
Running and running properly are two different things. Would you want to take a chance with a product that does what DW does? tongue


On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
Re: Time Machine error: spurious?
Ira L #42989 12/01/16 08:26 PM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Ira L
Running and running properly are two different things. Would you want to take a chance with a product that does what DW does? tongue

As I said, "Naaah", but on the other hand, I'm not 100% certain that there'd be any risk involved if I didn't go past Preview, in which case DW wouldn't actually be doing what it does (if, as I believe, its first pass is no more than a read).

I dunno, I'll think about taking a shot with a clone to see what happens, but my DW disc went bad, and I'm not sure I can run the app under any circumstances.

(The poster who ran it wasn't even aware that it wasn't supported despite his adamantly proactive attitude towards app updates/grades; I was just reporting that he did, and with no apparent repercussions.)


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #42992 12/01/16 09:21 PM
Joined: Aug 2009
Likes: 16
Moderator
Offline
Moderator

Joined: Aug 2009
Likes: 16
As long as no write operation is performed running the analysis should be safe. In fact Micromat's Checkmate relies on exactly that. But Apple has a well established habit of adding new features and functions to the file system. Therefore DiskWarrior, TechTool Pro, and Drive Genius are all OCD about running on any OS version they have not been tested on and certified safe. For the same reason even though running the analysis should be safe those same changes could easily cause those utilities to report either false negatives or false positives.

Disk Utility is no great shakes at repairing damaged file and volume structures but it is pretty good at finding and reporting errors. Unless and until I have a certified copy of DW, TTP, or DG I stick to Disk Utility for finding file and volume errors and if an error is found, hope DU will be capable of making the necessary repairs. Does that work? All I can say is, "so far, so good."


If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein
Re: Time Machine error: spurious?
joemikeb #42997 12/02/16 07:28 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: joemikeb
As long as no write operation is performed running the analysis should be safe. In fact Micromat's Checkmate relies on exactly that. But Apple has a well established habit of adding new features and functions to the file system. Therefore DiskWarrior, TechTool Pro, and Drive Genius are all OCD about running on any OS version they have not been tested on and certified safe. For the same reason even though running the analysis should be safe those same changes could easily cause those utilities to report either false negatives or false positives.

Your caveats have been posted before, but they're always worth repeating and are always appreciated when they are.

They're irrelevant in this instance, though, because my only reason for running my outdated version of DW would be to see if Carbon Copy Cloner can see the Preview volume to clone it; it doesn't even matter if DW returns inaccurate info so long as it gets to that volume with the magnifying glass icon.


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
Virtual1 #43019 12/04/16 12:49 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Virtual1
Originally Posted By: artie505
It'd be nice if I had DW to play with. (Hmmm... I wonder if running an older version will be dangerous if I don't go past Preview? Naaah, not even worth trying.)

DW is a bit OCD on that, it won't run on a disk that it can tell was used by an OS that's beyond the version it supports.

I just rolled out DiskWarrior v 4.4 (unsupported in El Cap) and ran it from an El Cap volume on its clone, and DW got to Preview with no issues, and getting to the point, Carbon Copy Cloner saw the Preview volume (with the magnifying glass), but it didn't see the volume itself.

Edit: CCC can't see it because it's unmounted when DW is in Preview mode.

Last edited by artie505; 12/04/16 06:41 AM.

The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #43036 12/05/16 05:54 PM
Joined: Aug 2009
Likes: 8
Offline

Joined: Aug 2009
Likes: 8
So does this mean CCC could make a clone of the Preview volume, if need be?


On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
Re: Time Machine error: spurious?
Ira L #43043 12/06/16 07:12 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Ira L
So does this mean CCC could make a clone of the Preview volume, if need be?

'Til now, I had gone no further than determining that CCC would allow me to select the Preview volume as a source, but since you asked, I installed DW for the 4th time...

(I ran unsupported DW v 4.4 [the final version was 4.6] on an El Cap volume.)
  • The Preview volume was the exact same size as the volume on which I ran DW.
  • CCC allowed me to select the Preview volume as a source, and the cloning operation completed.
  • I was able to boot into the clone (but I didn't do any testing).
  • Cloning the Preview volume to an essentially empty volume took 26 1/2 minutes compared to the 1 1/4 minutes it took to clone the original to the same volume.
  • When CCC cloned the Preview volume it apparently cloned even the empty space, because with SafetyNet on, the pre-existing data on my destination volume (both source and destination were 50 GB) was overwritten, whereas cloning the original volume under the same circumstances left it intact.
And finally, NO, I've got no intention of running my unsupported version of DW as a tool; should a need for such arise I'll buy the upgrade.


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire
Re: Time Machine error: spurious?
artie505 #43053 12/06/16 05:20 PM
Joined: Aug 2009
Likes: 8
Offline

Joined: Aug 2009
Likes: 8
Thanks for taking the time and effort to check this. smirk


On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
Re: Time Machine error: spurious?
Ira L #43065 12/07/16 12:30 AM
Joined: Aug 2009
Likes: 15
Online

Joined: Aug 2009
Likes: 15
Originally Posted By: Ira L
Thanks for taking the time and effort to check this. smirk

Been meaning to look into it for at least 5 years since V1 posted the possibility. smirk


The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire

Moderated by  alternaut, dkmarsh, joemikeb 

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.4
(Release build 20200307)
Responsive Width:

PHP: 7.4.33 Page Time: 0.038s Queries: 58 (0.027s) Memory: 0.6971 MB (Peak: 0.8503 MB) Data Comp: Zlib Server Time: 2024-03-28 14:20:04 UTC
Valid HTML 5 and Valid CSS