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Disk Utility First Aid problem

After experiencing a strange monitor flicker on bootup I ran first Aid in Disk Utility and received this report of corruption with two repairs that could not be made. An Apple chat support tech advised me to erase my entire computer and restore from my backup. But on telephoning Apple Support and letting that tech view my monitor with screen sharing she told me not to bother bcause everything seemed OK. Can anyone decipher this screen shot of the relevant part of the First Aid report which starts with checking a Time Machine snapshot?

Checking snapshot 1 of 1 (com.apple.TimeMachine.2021-11-05-075847.local)

warning: Cross Check : Mismatch between extentref entry reference count (2) and calculated fsroot entry reference count (1) for extent

(62609796 + 4)

warning: Cross Check: Count not mark range (62609796 + 4) allocated : File exists

warning: Cross Check : Mismatch between extentref entry reference count (2) and calculated fsroot entry reference count (1) for extent

(62609872 + 4)

warning: Cross Check: Count not mark range (62609872 + 4) allocated : File exists

Checking the extent ref tree.

Checking the document ID tree.

Checking the fsroot tree.

Checking the file key rolling tree.

Verifying volume object map space.

The volume /dev/rdisk3s5 was found to be corrupt and needs to be repaired.

Checking volume /dev/rdisk3s6.

Checking the APFS volume superblock.

Checking the object map.

Checking the snapshot metadata tree.

Checking the snapshot metadata.

Checking the extent ref tree.

Checking the fsroot tree.

Verifying volume object map space.

The volume /dev/rdisk3s6 appears to be OK.

Verifying allocated space.

Performing deferred repairs.

error: missing/invalid physical extent (62609796 + 4) with refcnt 1 at snapshot 782987

Skipped 2/2 repairs of this type in total.

The container /dev/diskOs2 appears to be OK.

Storage system check exit code is 0.

Operation successful.

Mac mini, macOS 12.0

Posted on Nov 6, 2021 1:53 PM

Reply
Question marked as Top-ranking reply

Posted on Nov 7, 2021 5:13 AM

Holger Jensen wrote:

After experiencing a strange monitor flicker on bootup I ran first Aid in Disk Utility and received this report of corruption with two repairs that could not be made. An Apple chat support tech advised me to erase my entire computer and restore from my backup. But on telephoning Apple Support and letting that tech view my monitor with screen sharing she told me not to bother bcause everything seemed OK. Can anyone decipher this screen shot of the relevant part of the First Aid report which starts with checking a Time Machine snapshot?
Checking snapshot 1 of 1 (com.apple.TimeMachine.2021-11-05-075847.local)
warning: Cross Check : Mismatch between extentref entry reference count (2) and calculated fsroot entry reference count



Screen flickering on boot up or shut down — I do not see this glitch as an issue, and would not try to drill down on this as a problem.



Snapshot warnings are not correlated.

If you run your Time Machine to your external drive I would expect it to clear local snapshots.



From the Terminal   look at  Time machine local snapshots, copy & paste:

tmutil listlocalsnapshots /


# tmutil listlocalsnapshots /


com.apple.TimeMachine.2017-10-04-014927 (dataless)

com.apple.TimeMachine.2017-10-04-024750

com.apple.TimeMachine.2017-10-04-024752

com.apple.TimeMachine.2017-10-04-024835

com.apple.TimeMachine.2017-10-04-024852



here is an example to delete  one by one from the above output list.

sudo tmutil deletelocalsnapshots 2017-10-04-014927



About Time Machine local snapshots - Apple Support





Similar questions

2 replies
Question marked as Top-ranking reply

Nov 7, 2021 5:13 AM in response to Holger Jensen

Holger Jensen wrote:

After experiencing a strange monitor flicker on bootup I ran first Aid in Disk Utility and received this report of corruption with two repairs that could not be made. An Apple chat support tech advised me to erase my entire computer and restore from my backup. But on telephoning Apple Support and letting that tech view my monitor with screen sharing she told me not to bother bcause everything seemed OK. Can anyone decipher this screen shot of the relevant part of the First Aid report which starts with checking a Time Machine snapshot?
Checking snapshot 1 of 1 (com.apple.TimeMachine.2021-11-05-075847.local)
warning: Cross Check : Mismatch between extentref entry reference count (2) and calculated fsroot entry reference count



Screen flickering on boot up or shut down — I do not see this glitch as an issue, and would not try to drill down on this as a problem.



Snapshot warnings are not correlated.

If you run your Time Machine to your external drive I would expect it to clear local snapshots.



From the Terminal   look at  Time machine local snapshots, copy & paste:

tmutil listlocalsnapshots /


# tmutil listlocalsnapshots /


com.apple.TimeMachine.2017-10-04-014927 (dataless)

com.apple.TimeMachine.2017-10-04-024750

com.apple.TimeMachine.2017-10-04-024752

com.apple.TimeMachine.2017-10-04-024835

com.apple.TimeMachine.2017-10-04-024852



here is an example to delete  one by one from the above output list.

sudo tmutil deletelocalsnapshots 2017-10-04-014927



About Time Machine local snapshots - Apple Support





Disk Utility First Aid problem

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