Doubt when creating a user and checking /etc/group and /etc/passwd

rosepower · 04-17-2007, 05:55 PM

Hi,

I've been having some doubts regarding the creation of users in slackware, and in general linux as well.

I installed Slackware, performed all the configuration that i think i need to do, so that the system performs like i want. And every thing went fine. I then used the script adduser to create my personal account on the system. I only entered my login and user name, the rest i accepted the default options.

Every thing is working fine but there is something troubling me:

When i run the command "id" i get this:
uid=1000(ricardo) gid=100(users) groups=11(floppy),17(audio),18(video),19(cdrom),100(users)

But when i check the /etc/group file my name is nowhere in the file:
root::0:root
bin::1:root,bin,daemon
daemon::2:root,bin,daemon
sys::3:root,bin,adm
adm::4:root,adm,daemon
tty::5:
disk::6:root,adm
lp::7:lp
mem::8:
kmem::9:
wheel::10:root
floppy::11:root
mail::12:mail
news::13:news
uucp::14:uucp
man::15:
audio::17:
video::18:
cdrom::19:
games::20:
slocate::21:
utmp::22:
smmsp::25:smmsp
mysql::27:
rpc::32:
sshd::33:sshd
gdm::42:
shadow::43:
ftp::50:
pop::90

op
scanner::93:
nobody::98:nobody
nogroup::99:
users::100:
console::101:

Should i not see my name in front of the groups i belong to, like audio, video, etc ???

Since i come from a windows background, there are still some concepts that i find hard to get into my head.

Best regards

H_TeXMeX_H · 04-17-2007, 06:01 PM

you are not a group ... user and group are two different things

erklaerbaer · 04-17-2007, 06:06 PM

what beats me though, is why you are in any group at all.
could it be, that that is /etc/groups-(a backup file) and not /etc/group?

(read slackbook.org)

H_TeXMeX_H · 04-17-2007, 06:26 PM

my '/etc/group' is exactly the same ... reading 'man group' it says no one keeps this file up-to-date ... so don't worry about it

rosepower · 04-17-2007, 06:31 PM

Hi again,

Maybe i'm mixing things, but when i create a user that user is added to /etc/passwd like this file that i have in my system (the last one is the user i created):

root:x:0:0::/root:/bin/bash
bin:x:1:1:bin:/bin:
daemon:x:2:2:daemon:/sbin:
adm:x:3:4:adm:/var/log:
lp:x:4:7:lp:/var/spool/lpd:
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/:
news:x:9:13:news:/usr/lib/news:
uucp:x:10:14:uucp:/var/spool/uucppublic:
operator:x:11:0

perator:/root:/bin/bash
games:x:12:100:games:/usr/games:
ftp:x:14:50::/home/ftp:
smmsp:x:25:25:smmsp:/var/spool/clientmqueue:
mysql:x:27:27:MySQL:/var/lib/mysql:/bin/bash
rpc:x:32:32:RPC portmap user:/:/bin/false
sshd:x:33:33:sshd:/:
gdm:x:42:42:GDM:/var/state/gdm:/bin/bash
pop:x:90:90:POP:/:
nobody:x:99:99:nobody:/:
ricardo:x:1000:100:Ricardo R,,,:/home/ricardo:/bin/bash

Now for the /etc/group file, i believe this is the form:
group name : group password : group ID: users

So if this is true in the /etc/group file, and according to the output of the id command, i should see something like this:
floppy::11:root,ricardo
audio::17:ricardo
video::18:ricardo
cdrom::19:ricardo
users::100:ricardo

regards

rosepower · 04-17-2007, 06:34 PM

@H_TeXMeX_H

Sorry i was writing as you replied.

What you said makes me wondering. If the group file, where you are supposed to add members to the groups is not up-to-date, how does the computer know wich groups i belong to ???

Have to check the script for adding the user !!!

Regards

gilead · 04-17-2007, 08:09 PM

You should be seeing your user name against the extra groups that you're a member of. This is from one of my boxes:

Code:

$ id
uid=1000(steve) gid=102(steve) groups=18(video),102(steve),117(cvs_st)
$ grep steve /etc/group
video::18:disk,steve
steve:x:102:
cvs_st:x:117:steve,cvsadmin

Could it be as erklaerbaer suggested that you're looking in /etc/group- instead of /etc/group?

rosepower · 04-18-2007, 03:24 AM

Hi,

Well, that was the result of "cat /etc/group", so i think it's correct.

I'll try the grep command later when i get home this evening.

Regards

rworkman · 04-18-2007, 09:49 AM

See /etc/login.defs for this line:
CONSOLE_GROUPS floppy:audio:video:cdrom

When you log in on a console, you are automatically added to these groups - that's why you don't see yourself listed on them in /etc/group.

You don't see yourself listed in the "users" group because that is your primary group. If you create a new user, and when it asks if you want to invite/add the user to any other groups, specify "wheel" or some other group, then look at /etc/group and you'll see that the user is listed beside that group name.

Have a look at login.defs(5) for more information.

rosepower · 04-18-2007, 05:56 PM

Hi,

Yep, that was it. Thanks a lot !!!

Always learning

Regards