Ubuntu – groups: cannot find name for group ID #########

users

This is a variant of the unresolved
https://askubuntu.com/questions/295610/cannot-find-name-for-group-id-26739201
but I'll post it here again since I have some more information

I recently made a fresh installation of 14.04 so most things "should" be clean.

When I open the terminal, I get this error message

groups: cannot find name for group ID ######

The group number changes every time I log out and log in again:

###### = 1097638658
###### = 1097638674
###### = 1097638677
###### = 1097638680
###### = 1097638683
###### = 1097646472 (here I also rebooted)

on subsequent logins.

At the same time I notice that I have problems creating new users from the settings menu.
I can create new users but not set their password. If I let the new users be without password I get kicked out whenever I try to log in with them.

Any ideas?

[EDIT]

Starting the shell (today) and asking for id I get

groups: cannot find name for group ID 1097972621
mikael@glasbult:~$ id
uid=1000(mikael)gid=1000(mikael),groups=1000(mikael),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),108(lpadmin),124(sambashare),1097972621

At the end out the output I notice a matching id: 1097972621

[NEW INFO]

Not sure if I should answer my own question or put it here. I mentioned the problem to my local sysadmin and he said the strange group number is an AFS-artefact. It's necessary for PAG, which gives a user the same rights in all sub-shell.
Thus it's not an error, just an ugly nuisance.

Case closed I suppose.

Best Answer

I have a similar issue on a machine I'm provisioning, but I don't yet know how to solve the problem directly, which in my case involves LDAP group enumeration.

However, /etc/bash.bashrc has a configurable flag to disable the section of bashrc that checks to see whether it should remind you how to use sudo. It is that section of bashrc that calls groups(1), which generates the error you are seeing.

To disable that check, and thus work around this error message, you can:

touch ~/.hushlogin

A) Short answer

Default groups; say for user123, on fresh install - (use command groups in a terminal):

user123 adm cdrom sudo dip plugdev lpadmin sambashare

Gives diff from 11.04 as

admin is replaced by sudo
dialout is removed
dip is added.

To get/view defaults. Would probably work for various others too; do:

sudo grep user-setup /var/log/installer/syslog

B) Restoring default groups

(Adding this to make it more complete)

1. Identifying the groups

I always set root password, but if you haven't use a live CD, live USB, other install etc. to get to the file.

If you have set root password (by i.e.):

sudo passwd root

and have lost sudo privileges do:

su - root
grep user-setup /var/log/installer/syslog

Gives you i.e.

... user-setup: pwconv: failed to change the mode of /etc/passwd- to 0600
... user-setup: Shadow passwords are now on.
... user-setup: Adding user `user123' ...
... user-setup: Adding new group `user123' (1000) ...
... user-setup: Adding new user `user123' (1000) with group `user123' ...
... user-setup: Creating home directory `/home/user123' ...
... user-setup: Copying files from `/etc/skel' ...
... user-setup: addgroup: The group `lpadmin' already exists as a system group. Exiting.
... user-setup: Adding group `sambashare' (GID 124) ...
... user-setup: Done.
... user-setup: Adding user `user123' to group `adm' ...
... user-setup: Adding user user123 to group adm
... user-setup: Done.
... user-setup: Adding user `user123' to group `cdrom' ...
... user-setup: Adding user user123 to group cdrom
... user-setup: Done.
... user-setup: Adding user `user123' to group `dip' ...
... user-setup: Adding user user123 to group dip
... user-setup: Done.
... user-setup: Adding user `user123' to group `lpadmin' ...
... user-setup: Adding user user123 to group lpadmin
... user-setup: Done.
... user-setup: Adding user `user123' to group `plugdev' ...
... user-setup: Adding user user123 to group plugdev
... user-setup: Done.
... user-setup: Adding user `user123' to group `sambashare' ...
... user-setup: Adding user user123 to group sambashare
... user-setup: Done.
... user-setup: adduser: The group `debian-tor' does not exist.
... user-setup: Adding user `user123' to group `sudo' ...
... user-setup: Adding user user123 to group sudo
... user-setup: Done.
... ubiquity: Removing user-setup ...
... ubiquity: Purging configuration files for user-setup ...

Or:

su - root
grep "user-setup: Adding user user123 to group" /var/log/installer/syslog | cut -d' ' -f11

Which yields:

adm
cdrom
dip
lpadmin
plugdev
sambashare
sudo

(No idea why dip suddenly has become a default group by install. Something to do with dialout being removed?)

2.a Updating groups - using "built-in" root access

So do, as root, to add groups to user, i.e. user user123:

usermod -a -G adm,cdrom,lpadmin,sudo,sambashare,dip,plugdev user123

Where (Somewhat outdated on 12.10):

adm         Monitor system logs
cdrom       Use CD-ROM drives
lpadmin     Configure printers
sudo        administer the system, ...
sambashare  Share files with the local network
dip         Connect to the Internet using a modem
plugdev     Access external storage devices

Some extras you might need: (check what you have by root@YOURPC:~# id -nG user123)

dialout     ttyS*/Serial/COM1,COM2 ...
vboxusers   Virtual Box
user123     Your own group

If you want; double-check /etc/group , i.e. (here with some extras):

root@YOURPC:~# grep user123 /etc/group

adm:x:4:user123
audio:x:29:user123,timidity,pulse
video:x:44:user123
lp:x:7:user123
dialout:x:20:user123
cdrom:x:24:user123
sudo:x:27:user123
dip:x:30:user123
plugdev:x:46:user123
lpadmin:x:107:user123
user123:x:1000:
sambashare:x:124:user123
vboxusers:x:127:user123
autologin:x:1001:user123

As an alternative one can boot in to rescue mode and

mount -o remount,rw /
usermod -G adm,cdrom,lpadmin,sudo,sambashare,dip,plugdev user123

Log out and log in. Groups should be updated.

2.b Updating groups - using root access from Live-CD etc.

xxx here is where your file-system is mounted when running a live edition, i.e. /media/foo.

Manually edit the file /xxx/etc/group using vigr and add user as in previous listing.

Or; only add user to sudo; as in:

sudo:x:27:user123

Boot into your installation and update by executing the usermod command with sudo:

sudo usermod -a -G adm,cdrom,lpadmin,sudo,sambashare,dip,plugdev user123

Log out and log in. Groups should be updated.

Double Note: admin is no longer part of Ubuntu as of 11.10 in favour of sudo.

Best Answer

Related Solutions

Ubuntu – Change user’s primary group – have new files made in that group

Ubuntu – Default groups for user in Ubuntu

A) Short answer

B) Restoring default groups

1. Identifying the groups

2.a Updating groups - using "built-in" root access

2.b Updating groups - using root access from Live-CD etc.

Related Question