The old post shows how to add a user to a specific group. From time to time, I need to remove a user from a specific group. So here what I summarize how to do this.

2009/06/29 - [computer/linux] - add a user to a specific group


remove a user from a specific group

Here auser is the fake account to be removed from www-data group

Step 1

# vigr

change  from   auser:x:1001:www-data  to    auser:x:1001:

Then they will ask and notice the following messages:

You have modified /etc/group.

You may need to modify /etc/gshadow for consistency.

Please use the command 'vigr -s' to do so.


Step 2

 # vigr -s


You have modified /etc/gshadow.

You may need to modify /etc/group for consistency.

Please use the command 'vigr' to do so.


Step 3

Check group whether it is or not

# tail /etc/group

.....

utempter:x:119:

auser:x:1001:




posted by citadel
Alsa error messages :
alsa−lib: pcm_dmix.c:831:(snd_pcm_dmix_open) unable to create IPC semaphore


Solution :

open /etc/group file


audio:x:29:username1,username2

for virtualbox



logout and login
posted by citadel