<< Solved >> The partition map needs to be repaired because there's a problem with EFI system partition's file system.

[sanigo]

After upgrade to 14.15,I used the disk util to check disk for errors, get:
The partition map needs to be repaired because there's a problem with EFI system partition's file system.

I use usb to boot, and use diskutil to fix the partition. But the problem remains after reboot.

 

[sanigo]

I used the following to fix the problem:
sudo fsck_msdos disk0s1

 

[pibefision]

Thanks for sharing. FSK_MDOS fixed it to mee too.

 

[maryhack2018]

Me too, thanks @sanigo !!!, ... in my case the bit command adjustment is ...

sudo fsck_msdos disk1s1

... according to my boot EFI partition located in disk1s1

 

[PliSsK]

I found this issue with the EFI partition whilst running DU although otherwise the system was working normally. I did the above terminal operation in OS X and immediately afterwards both my OS X and Windows 10 partitions became unstable, particularly Windows, and now Windows has gotten so bad it is totally unusable. I was getting various Windows hardware errors and it freezed in Windows approximately 30 to 60 seconds after log in. OS X was resetting about 50-70% of the time during boot up. I did fsck on the EFI partition in Linux to fix it. This fixed OS X but not Windows which I suspect was completely scrambled by this point. I was not able to keep Windows long enough to reinstall it whilst keeping the files so I elected to wipe Windows completely and now it is finally running normally again. I wish I had just left it alone!

 

[rambird]

Brilliant, thank you you...I had the same problem. Now solved.

 

[Rajkhand]

@sanigo in Big Sur it is not working I get

** /dev/rdisk5s1 (NO WRITE)
** Phase 1 - Preparing FAT
** Phase 2 - Checking Directories
** Phase 3 - Checking for Orphan Clusters
Found orphan cluster(s)
Fix? no
Found 37226 orphaned clusters
1056 files, 81178 KiB free (162357 clusters)

The disk is shown as (NO WRITE)

it is the external USB Big Sur install USB stick

What is the solution?

 

[Jithin.C.V]

@sanigo in Big Sur it is not working I get

** /dev/rdisk5s1 (NO WRITE)
** Phase 1 - Preparing FAT
** Phase 2 - Checking Directories
** Phase 3 - Checking for Orphan Clusters
Found orphan cluster(s)
Fix? no
Found 37226 orphaned clusters
1056 files, 81178 KiB free (162357 clusters)

The disk is shown as (NO WRITE)

it is the external USB Big Sur install USB stick

What is the solution?

Please share the full output of below command to re-check. Normally your Target device will be named as /dev/diskXsY format. NOT /dev/rdsk

diskutil list

 

[Rajkhand]

Please share the full output of below command to re-check. Normally your Target device will be named as /dev/diskXsY format. NOT /dev/rdsk

diskutil list

You are very observant, I missed that but let me assure you that it is disk5s1 I was using in the command. I’ll send you again both the command and the output in the morning

 

[Rajkhand]

@Jithin.C.V

when trying to make the disk mount read-write I was trying different commands to mount the volume
but in both ways to mounting an efi partition the results are the same. Probably the r stands for ReadOnly?

iMac:~ raj$ sudo mkdir /Volumes/efi
Password:
iMac:~ raj$ sudo mount -rw -t msdos /dev/disk5s1 /Volumes/efi
iMac:~ raj$ sudo fsck_msdos /dev/disk5s1
** /dev/rdisk5s1 (NO WRITE)
** Phase 1 - Preparing FAT
** Phase 2 - Checking Directories
** Phase 3 - Checking for Orphan Clusters
Found orphan cluster(s)
Fix? no
Found 37226 orphaned clusters
1085 files, 80944 KiB free (161889 clusters)

also the same with

iMac:~ raj$ sudo diskutil mount /dev/disk5s1
Volume EFI on /dev/disk5s1 mounted
iMac:~ raj$ sudo fsck_msdos /dev/disk5s1
** /dev/rdisk5s1 (NO WRITE)
** Phase 1 - Preparing FAT
** Phase 2 - Checking Directories
** Phase 3 - Checking for Orphan Clusters
Found orphan cluster(s)
Fix? no
Found 37226 orphaned clusters
1072 files, 80987 KiB free (161974 clusters)