sudo: can't open /private/etc/sudoers: Permission denied | sudo: no valid sudoers sources found, quitting

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Level 1

59 points

sudo: can't open /private/etc/sudoers: Permission denied | sudo: no valid sudoers sources found, quitting

Hi,

I've had this problem before on an old machine and managed to fix it quite quickly, but the things I tried before don't seem to be working on this machine.

Basically, when I go in to Terminal and try running something with sudo, it just echoes:

sudo: can't open /private/etc/sudoers: Permission denied

sudo: no valid sudoers sources found, quitting

I also get the same message when booted in to Single user mode, thinking it might just have been an issue with my users id. I have already tried changing the file permissions, editing the sudoers file to add in my local users record etc...... but then it just gives me a different error message (eventually coming back to the above when I try changing something else to fix it).

I've run Applejack and Diskutility, but as expected they don't work either........

Any help would be much appreciated!- my new MacBook Pro won't even install anything requiring root permissions any longer, giving the same error message in the /var/log/install.log! :-(

As you can understand, I'm very upset because it is a new machine, and I have no idea what would have caused this to happen. The usual cause is editing the sudoers file without using visudo, but I can never recall doing that.

I need my root access back! 😟

Kind regards,

Aidan

iMac, Mac OS X (10.7.2), Hardware Serial: VM*****B9S

Posted on Jan 24, 2012 6:31 AM

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Answer 1

paulfox

Level 1

8 points

Jun 3, 2017 9:58 PM in response to Joshua Brown1

I used these instructions in El Capitan with excellent success. To understand the command better I found this response to the same question I had about it. I cheated and didn't read the man pages though.

https://askubuntu.com/questions/29589/chmod-ux-versus-chmod-x

My problem happened because instead of doing a drive replacement and restoration from a backup, I preferred to try a disk clone and simple swap. Each has respective challenges and benefits which aren't really appropriate to go into here. I'm just giving background as to HOW I came to this issue.

Many thanks to Joshua Brown for the well written resolution.

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Answer 2

Camelot

Level 9

54,333 points

Jan 24, 2012 2:23 PM in response to AidanBW

Well, the most obvious question is - what are the permissions on the file?

Since it's complaining about 'Permission denied', that would seem to be the first thing to check....

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Answer 3

Linc Davis

Level 10

209,535 points

Jan 24, 2012 4:41 PM in response to AidanBW

Back up all data, if not already done. Boot from your recovery partition (command-R at startup) and reinstall Lion. If you upgraded from 10.6, you'll need the Apple ID and password you used to buy Lion from the App Store. Don't erase the boot volume; just reinstall in place. You won't need your backup unless something goes wrong.

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Answer 4

AidanBW Author

Level 1

59 points

Jan 25, 2012 4:27 AM in response to Camelot

Hi, thanks for the quick reply.

I've them set to 0440 (how they should be).

-------------------------------------------------------------------------------- ------------------------------------------------

ls -l /private/etc/sudoers

-r--r-----@ 1 root wheel 2869 24 Jan 13:17 /private/etc/sudoers

ls -le /private/etc/sudoers

-r--r-----@ 1 root wheel 2869 24 Jan 13:17 /etc/sudoers

0: user:a27aida allow read,write,append,readattr,writeattr,readextattr,writeextattr,readsecurity

id a27aida

uid=501(a27aida) gid=20(staff) groups=20(staff),403(com.apple.access_ssh),12(everyone),33(_appstore),61(locala ccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),100(_lpopera tor),204(_developer),402(com.apple.sharepoint.group.1)

-------------------------------------------------------------------------------- ------------------------------------------------

(Same output as in this post: https://discussions.apple.com/thread/2789552?start=0&tstart=0 )

Think I'm just going to have to go for the fresh install........ 😟 - as there are lots of other discussions to do with this topic, and none have been resolved.

Thanks for you help anyway!

A

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Answer 5

AidanBW Author

Level 1

59 points

Jan 25, 2012 4:29 AM in response to Linc Davis

Looks like it's my only option......... 😐

Thanks,

A

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Answer 6

BobHarris

Level 9

52,979 points

Jan 25, 2012 5:26 AM in response to AidanBW

My Lion sudoers file looks like

/bin/ls -leO@ /private/etc/sudoers
-r--r-----  1 root  wheel  compressed 1275 Oct  8 01:19 /private/etc/sudoers

I think you can ignore the compressed.

I do not have any ACLs or other attributes on the file.

The contents of my sudoers file is

# sudoers file.
#
# This file MUST be edited with the 'visudo' command as root.
# Failure to use 'visudo' may result in syntax or file permission errors
# that prevent sudo from running.
#
# See the sudoers man page for the details on how to write a sudoers file.
#


# Host alias specification


# User alias specification


# Cmnd alias specification


# Defaults specification
Defaults        env_reset
Defaults        env_keep += "BLOCKSIZE"
Defaults        env_keep += "COLORFGBG COLORTERM"
Defaults        env_keep += "__CF_USER_TEXT_ENCODING"
Defaults        env_keep += "CHARSET LANG LANGUAGE LC_ALL LC_COLLATE LC_CTYPE"
Defaults        env_keep += "LC_MESSAGES LC_MONETARY LC_NUMERIC LC_TIME"
Defaults        env_keep += "LINES COLUMNS"
Defaults        env_keep += "LSCOLORS"
Defaults        env_keep += "SSH_AUTH_SOCK"
Defaults        env_keep += "TZ"
Defaults        env_keep += "DISPLAY XAUTHORIZATION XAUTHORITY"
Defaults        env_keep += "EDITOR VISUAL"
Defaults        env_keep += "HOME MAIL"


# Runas alias specification


# User privilege specification
root    ALL=(ALL) ALL
%admin  ALL=(ALL) ALL


# Uncomment to allow people in group wheel to run all commands
# %wheel        ALL=(ALL) ALL


# Same thing without a password
# %wheel        ALL=(ALL) NOPASSWD: ALL


# Samples
# %users  ALL=/sbin/mount /cdrom,/sbin/umount /cdrom
# %users  localhost=/sbin/shutdown -h now

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Answer 7

Feb 29, 2012 11:23 PM in response to AidanBW

Thank you for the suggestion. I found the fix - I re-installed Lion from the recovery system. It was the only thing that worked and, after that, Adobe stuff installed OK.

It didn't fix, sadly, the graphics hang/crash kernel panic problem.

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Answer 8

Apr 15, 2012 11:16 AM in response to AidanBW

I had this exact problem. It was due to the group execute bit being set to 0 on the root directory (not /private, not /private/etc). Be sure that both the owner and group execute bits of the directories containing /private/etc are all set to true, otherwise sudo won't be able to open the sudoers file.

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Answer 9

May 24, 2012 7:48 AM in response to Adam Wenocur

Adam's solution worked perfectly for me!

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Answer 10

yb11

Level 1

0 points

Aug 23, 2012 4:35 AM in response to Adam Wenocur

it worked for me.

I couldn't sudo after an upgrade to Lion from 10.6.

it seems it also solved stability issues.

precisely i added the execute permission to users within the administrative group, in a terminal

> su (type your root password)

> chmod g+x /

> exit

I hope it is safe, feel free to correct me!

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Answer 11

Nov 28, 2012 11:22 PM in response to Adam Wenocur

Adam Wenocur wrote:

I had this exact problem. It was due to the group execute bit being set to 0 on the root directory (not /private, not /private/etc). Be sure that both the owner and group execute bits of the directories containing /private/etc are all set to true, otherwise sudo won't be able to open the sudoers file.

I am having the same issue when installing Acrobat XI.

How exactly to you do what you mentionned ?

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Answer 12

Nov 30, 2012 4:34 PM in response to macktruck

Enter the commands yb11 posted above on a shell prompt (via the Terminal application). If that doesn't solve the problem, adding these other commands may help:

> chmod g+x /private

> chmod g+x /private/etc

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Answer 13

Dec 1, 2012 2:26 AM in response to Adam Wenocur

Thanks!

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Answer 14

Apr 18, 2013 6:37 AM in response to Adam Wenocur

Hey, can you please help me. I just want to edit my host file to be able to downgrade my iphone. I did that without any problems a couple of weeks ago with "sudo nano /etc/hosts" , but now I get:

sudo: can't open /private/etc/sudoers: Permission denied

sudo: no valid sudoers sources found, quitting

I am Admin, I tried it with the root account, I fixed the access rights of the hdd and I changed, enabled and disabled file Sharing. My Macbook Pro is running with Mountain Lion.

I know my english is not the best. And I am not really into commanding with the terminal and that kind of stuff but i´ll try my best.

Please tell me a way how to edit my hostfile!

Thak you all for any suggestions!

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Answer 15

Jun 5, 2013 5:50 AM in response to maxschlehuber

Did you try opening the Terminal app and entering the chmod lines mentioned above?

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