After updating to big sur, I can no longer mount the root as writable (even with SIP disabled):
sudo mount -uw /
mount_apfs: volume could not be mounted: Permission denied
mount: / failed with 66
How can I fix this?
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Sign up to join this communityAfter updating to big sur, I can no longer mount the root as writable (even with SIP disabled):
sudo mount -uw /
mount_apfs: volume could not be mounted: Permission denied
mount: / failed with 66
How can I fix this?
DISCLAIMER: have a good backup and plan to erase and reinstall your Mac from the internet before trying this procedure. A mistake can prevent your system from starting without assistance.
csrutil authenticated-root disable
mount
and chop off the last s, e.g. if your root is /dev/disk1s2s3
, you'll mount /dev/disk1s2
~/mount
mkdir -p -m777 ~/mount
sudo mount -o nobrowse -t apfs DISK_PATH MOUNT_PATH
, using the values from above
sudo mount -o nobrowse -t apfs /dev/disk1s2 ~/mount
sudo bless --folder MOUNT_PATH/System/Library/CoreServices --bootefi --create-snapshot
zsh
/ bash
/sh
whatever you need to run it? I cannot manage to get this working as mount_apfs: volume could not be mounted: Resource busy
failed with 75
Feb 5, 2021 at 1:05
/System/Library/LaunchDaemon/
with both SIP and SSV disabled (SSV = eclecticlight.co/2020/06/25/…), any modifications performed are not persisted once I boot back into OSX :/
Feb 12, 2021 at 2:12
bless
command) fails to even create a snapshot, much less bless it. I also tried another way to create a snapshot, /System/Library/Filesystems/apfs.fs/Contents/Resources/apfs_systemsnapshot -v <volume mount point> -r ""
from tonymacx86.com/threads/… but that also gave an error, so I rebooted back without a snapshot of my changes, and lost them all ..
Apr 28, 2021 at 16:05
authenticated-root
was not properly disabled. I run MacOS in VMWare, and disabled SIP using this guide: itectec.com/askdifferent/… but disabling authenticated-root
was missing from the hex value stored to NVRAM. Using value ff0f0000 instead of 7f000000 did the trick.
Apr 10, 2022 at 15:22
My company requires to read/write environment informations under /data/webapps/appenv
. Therefore, this workaround shared by a colleague of mine might not answer this question directly, but it is super useful if you want to write something under your root path!
Create a file: sudo vim /etc/synthetic.conf
.
Write content: <dir>⇥/System/Volumes/Data/<dir>
. Notice: the ⇥
is a tab!
In my case, it looks like this: data⇥/System/Volumes/Data/data
Go to /System/Volumes/Data
and do sudo mkdir <dir>
.
Then do sudo chmod -R 777 <dir>
.
Finally, reboot, and your directory <dir>
should now be accessible.
man synthetic.conf
or derflounder.wordpress.com/2020/01/18/…
Apr 3, 2021 at 18:55