Time Machine Problems

[Robert4]

Hi,

Thought it best to start a new Post re this, rather than appending my older one.

Have put many, many, hrs into trying to get Time Machine working, and
understanding all of its "nuances," which apparently there are many.
Driving me crazy.

Might be wrong, but i am convinced I am doing everything correctly, but...

Anyway, got it to fully backup my HD, about 250 GB worth to a new external WD drive.
Great.
But it's the incremental daily, or periodic backups, that it can't seem to do.

Keep getting error msgs such as:

Backup failed.
Time Machine couldn't back up to "Mac Time Machine Backup" (name of my ext. HD)
Details:

Time Machine couldn't complete the backup to Time Machine Backup

Unable to complete Backup.
**An error occurred while creating the backup folder. etc.

a. So, might anyone shed any light as to the "backup folder can't create" msg. ?
b. Is it doing some incremental backup(s), but not all that it thinks it should ?
(the "couldn't complete" msg. Is it likely doing "some" ?)
c. Any way of inspecting what files and folders it has incrementally backed up ?

d. Might the Time machine program be corrupted ?
If so, any way of downloading and installing a new fresh copy ?

Thanks for all the help with this; any and all thoughts would be most appreciated.
Bob

 

[Brian33]

Sounds frustrating. TM is great when it works properly (which it has for years, for me) but frustrating when something's wrong (my current situation, too)!

a. So, might anyone shed any light as to the "backup folder can't create" msg. ?
b. Is it doing some incremental backup(s), but not all that it thinks it should ?
(the "couldn't complete" msg. Is it likely doing "some" ?)

This may help -- it's a way to see some Time Machine log messages while a backup is running. Even when TM is working correctly, some errors will show up that you shouldn't worry about, but you will probably also see errors related to the folder or file that caused the backup to terminate. You have to use Terminal.app, and enter the following 'log' command line. Leave the Terminal window open, then manually start a TM backup. Messages will appear in real-time. Hit Ctl-C in Terminal to terminate the 'log' command.

log stream --style syslog --predicate 'senderImagePath contains[cd] "TimeMachine"' --info

c. Any way of inspecting what files and folders it has incrementally backed up ?

Hmmm. This question reminds me I think there is some sort of log saved within the backup snapshot database itself. Can't quite remember -- I'll try to go searching for it...

d. Might the Time machine program be corrupted ?
If so, any way of downloading and installing a new fresh copy ?

I think it's highly unlikely that the TM program itself is corrupted. Since it's installed as part of macOS, I don't know of a way to reinstall just that part.

One other idea: perhaps the external drive is unreliable? Do you have another drive you could use, even just temporarily to see if the problem(s) go away with a different external drive?

 

[ItWasNotMe]

For question c. Any way of inspecting what files and folders it has incrementally backed up ?

Response:

Use tmutil from the command line in a terminal session. There is a compare command.

Below is from the manual - you can also see this by starring a terminal session and typing "man tmutil"

Easiest way to use it is
1. Start terminal
2. Type "tmutil compare"
3. Drag two of the backup folders to the terminal window from a finder window (will substitute the full path name)

From the manual
-------------------
compare [-@acdefglmnstuEUX] [-D depth] [-I name] [snapshot_path | path1 path2]

Perform a backup diff.



If no arguments are provided, tmutil will compare the computer to

the latest snapshot. If a snapshot path is provided as the sole

argument, tmutil will compare the computer to the specified snap-

shot. If two path arguments are provided, tmutil will compare

those two items to each other. tmutil will attempt to inform you

when you have asked it to do something that doesn't make sense or

isn't supported.



The compare verb allows you to specify what properties to com-

pare. If you specify no property options, tmutil assumes a

default property set of -@gmstu. Specifying any property option

overrides the default set.



Options:

-a Compare all supported metadata.

-n No metadata comparison.

-@ Compare extended attributes.

-c Compare creation times.

-d Compare file data forks.

-e Compare ACLs.

-f Compare file flags.

-g Compare GIDs.

-m Compare file modes.

-s Compare sizes.

-t Compare modification times.

-u Compare UIDs.

-D Limit traversal depth to depth levels from the begin-

ning of iteration.

-E Don't take exclusions into account when comparing items

inside volumes.

-I Ignore paths with a path component equal to name during

iteration. This may be specified multiple times.

-U Ignore logical volume identity (volume UUIDs) when

directly comparing a local volume or snapshot volume to

a snapshot volume.

-X Print output in XML property list format.

 

[flugelgolf]

Here's what helped me. start with Robert above:
1, in Terminal type log stream --style syslog --predicate 'senderImagePath contains[cd] "TimeMachine"' --info
and Enter
2. Start a backup in TM. watch the Terminal "stream" and note all errors.
3. Then simply go to TM Options, and EXCLUDE any directories or files that are causing the problem.
You may have to repeat this step if there are multiple errors.

This fixed my problem (in High Sierra), as there was an error, EVERY TIME, in a /Google/Chrome/Default/syncdata. directory. I excluded that per the above, next TM worked great.

 

[Partron22]

I find Time Machine nice when I'm writing the great Amsrican Novak. Zip, Zop, Zoop, and that last hour I spent idolizing Mr. Right is gone. Course when I trash an app and hurt my directory structure , Time Machine fails and I have to thank my lucky stars that I also use SuperDuper.