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I have two users, user1 and user2, that are both members of groupA. user2 has a folder in their home directory called folderA. If they wish to allow read-write-execute permissions for all members of groupA, how would they do this?

What if folderA contains many files and additional folders that also need to have read-write-execute permission?

Information regarding groups is a little 'spotty' across the web, so I am putting my question here in the hope someone posts a clear answer that might help others out too.

Thanks!

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2 Answers2

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FolderA will first need to be part of groupA - the folder's owner or root can perform this operation

chgrp groupA ./folderA

Then groupA will need rwx permissions of the folder

chmod g+rwx  ./folderA

There are options in the chgrp and chmod commands to recurse into the directory if required.

Pablo Bianchi
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Charles Green
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    note: you should make sure that you can access intermediate directories too (+x might be enough). – jfs Aug 02 '16 at 09:55
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    I originally tried chown :groupname ./folder and that didnt work - as in it changed the group, but didn't give any effective permissions – user230910 Nov 17 '19 at 21:03
  • didn't worked for me also. Folder somehow can not give write permissions to a group. Whatever I have tried. – Gediminas May 21 '20 at 07:04
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    This did not work for me. – Scorb Nov 22 '20 at 23:12
  • @ScottF Can you list the properties of the directory with ls -l ./folderA to ensure that the group permissions were applied? – Charles Green Nov 24 '20 at 01:44
  • I followed these commands verbatim on Ubuntu 18.04.6 and on any member of the group, within the directory, on touch test.txt, I get the error: touch: cannot touch 'test.txt': Permission denied . I'm trying to give access to the group appowners. This is the output of ls -al : drwxrwxr-x 2 root appowners 4096 Apr 18 22:38 src . EDIT: The reason was, if a user is added to a new group, they must re-login to receive the new group permissions. – Caleb Jay Apr 18 '22 at 21:50
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    User and group permission changes do not take effect until you logout and login again (see answer below), you might even need to reboot if a folder is held open by a user having access on logout. At least IME, with much frustration, changes do not take place when you do chown/chgrp/chmod but only (loosely speaking) on reboot. Sometimes it might be enough to start a new shell, or new TTY, but a reboot definitely works. – pbhj Sep 11 '22 at 22:10
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    @pbhj That has not been my experience, although I will admit to not having great depth of experience. I do need to logout/in if I have altered the user or group - the login does not pickup altered permissions until the next login. But altered file and directory permissions work immediately for me. – Charles Green Sep 12 '22 at 14:45
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My own experience in this area here. Tested on Ubuntu 18.04.

Allow to write in the system folder

Give write permission to /etc/nginx/ folder.

# Check 'webmasters' group doen't exist
cat /etc/group | grep webmasters
# Create 'webmasters' group
sudo addgroup webmasters
# Add users to 'webmasters' group
sudo usermod -a -G webmasters username
sudo usermod -a -G webmasters vozman
sudo usermod -a -G webmasters romanroskach

Group assignment changes won't take effect


until the users log out and back in.


Create directory


sudo mkdir /etc/nginx/


Check directory permissions


ls -al /etc | grep nginx
drwxr-xr-x   2 root root     4096 Dec  5 18:30 nginx


Change group owner of the directory


sudo chgrp -R webmasters /etc/nginx/


Check that the group owner is changed


ls -al /etc | grep nginx
drwxr-xr-x   2 root webmasters   4096 Dec  5 18:30 nginx


Give write permission to the group


sudo chmod -R g+w /etc/nginx/


Check


ls -al /etc | grep nginx
drwxrwxr-x   2 root webmasters   4096 Dec  5 18:30 nginx


Try to create file


sudo -u username touch /etc/nginx/test.txt  # should work
sudo -u username touch /etc/test.txt  # Permission denied

Give write permission to /etc/systemd/system/ folder.

# List ACLs
getfacl /etc/systemd/system

getfacl: Removing leading '/' from absolute path names


file: etc/systemd/system


owner: root


group: root


user::rwx
group::r-x
other::r-x


Add 'webmasters' group to an ACL


sudo setfacl -m g:webmasters:rwx /etc/systemd/system


Check


getfacl /etc/systemd/system


getfacl: Removing leading '/' from absolute path names


file: etc/systemd/system


owner: root


group: root


user::rwx
group::r-x
group:webmasters:rwx
mask::rwx
other::r-x


sudo -u username touch /etc/systemd/system/test.txt  # should work
sudo -u username touch /etc/systemd/test.txt  # Permission denied

Original how-to.

Pablo Bianchi
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