Failed "First Aid" on an external SSD

Question

Failed "First Aid" on an external SSD

I use an external 120G SSD as Time Machine for my 120G MacBook Air - just now TM refused to run so I used Disk Utilities to do a "repair" - with the following error message resulting --

Repairing file system.

Volume was successfully unmounted.

Performing fsck_hfs -fy -x /dev/rdisk2s2Checking Journaled HFS Plus volume.

Checking extents overflow file.

Checking catalog file.

Invalid node structure

The volume Air TM-SSD could not be verified completely.

File system check exit code is 8.

Restoring the original state found as mounted.

Problem -69842 occurred while restoring the original mount state.

File system verify or repair failed.

Operation failed…

Any thoughts as to what is the problem, please.

Dan

Mac mini, macOS High Sierra (10.13), iPad Mini-2, Watch_1

Posted on Apr 20, 2018 2:11 PM

Reply

Answer 1

Top-ranking reply

Kappy

Level 10

362,017 points

Apr 20, 2018 2:51 PM in response to Dan Mitchell1

Invalid Node Structure is the problem, and it cannot be fixed by Disk Utility. It can be fixed by Disk Warrior. It can also be fixed by cloning the disk to another disk, erasing the disk, and clone the system back. It can be fixed by simply erasing the disk and making a fresh install of macOS.

Reply

Answer 2

Kappy

Level 10

362,017 points

Apr 20, 2018 4:25 PM in response to Dan Mitchell1

Not at all. It isn't a hardware problem but a software glitch or a directory corruption. BTW, the Time Machine backup is bootable. It has a hidden copy of your Recovery HD. You must boot as follows:

Boot Using OPTION key

Restart the computer.
Immediately after the chime press and hold down the "OPTION" key.
Release the key when the Boot Manager screen appears.
Select the disk icon of your Time Machine drive. It may start with "EFI Install" in the name.
Click on the arrow button under the drive icon.

This will boot into a Recovery HD from which you can run Disk Utility, install macOS, or restore from a Time Machine backup. It must be a full backup to be bootable. If not then you must first install macOS.

Reply

Answer 3

Apr 20, 2018 4:29 PM in response to Kappy

Fortunately the main internal 120G SSD drive reports back as OK, so I propose just to wipe the external SSD clean and restart using it as TM from the current state of the MacBook, or else just keep it as is and get another SSD to act as TM.

Reply

Answer 4

Kappy

Level 10

362,017 points

Apr 20, 2018 7:38 PM in response to Dan Mitchell1

Do not format the Time Machine SSD using APFS. It is not yet compatible with Time Machine. Use HFS+ instead: How to Skip Converting to APFS When Installing macOS High Sierra and Can APFS be used with Time Machine, Boot Camp, and File Vault?

Reply

Answer 5

Apr 20, 2018 2:53 PM in response to Kappy

The disk is my external Time Machine disk, so there is no operating system on it, only a TM file - it was when I wanted to "backup now", to run a manual backup, that the problem showed up.

Is this something peculiar to SSDs ? Cause ?

Reply

Failed "First Aid" on an external SSD

Similar questions