Anything related with user accounts and user management on Unix-like systems.

learn more… | top users | synonyms

3
votes
1answer
2k views

How do I add a local user to a box that uses LDAP authenticaiton?

I'm working with a box that uses LDAP for user authentication. However, I need to add a local user to run some services and I don't want non-person users junking up the LDAP directory. Does anyone ...
0
votes
2answers
212 views

Can't login into webmin on a VPS

I bought a VPS server, and I have installed webmin on it. When I want to login to webmin via: http://88.198.196.118:10000/ it will redirect me to: https://static.88-198-196-118.clients.your-...
3
votes
3answers
2k views

Killing other user processes

There are certain user environments in which we have to login during certain performance testing and and kill all the process running in that environment. The environment names are like rswrk01, … up ...
6
votes
5answers
3k views

Why is it recommended to create a group and user for some applications?

Most of the time, when installing a program from source it is recommended to create a new user and a new group and give /usr/local/<myapp> the recently created user and group ownership. Why is ...
5
votes
3answers
3k views

Changing the UID of files in /proc

In a follow up to this question about changing the UID of a user, it is recommended to change the ownership of all files on the system (this answer) find / -uid 1000 -exec chown 5000 '{}' \+ where ...
2
votes
1answer
249 views

Where can I find a reference to the format of the comment field (field 5) of the /etc/passwd file?

In the /etc/passwd file on my system, the "comment" field, field 5, is inconsistent in its contents. I thought that I could extract it to get the full name of the user. fullname=`awk -F: '$1 == name ...
8
votes
1answer
458 views

Why does the 'w' command show phantom logged in users?

On Linux (Fedora 14), the "w" command says this: [USERNAME@PC ~] w 23:51:32 up 13 min, 7 users, load average: 0,22, 0,42, 0,34 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT ...
1
vote
1answer
309 views

permission and user/group of a program executed through a script

I am curious, in the following scenario, what kind of permission does a shell script or Java program has (owner/group/other)? There is a script called run.sh, and it in turn calls a Java program a....
2
votes
1answer
421 views

How to create a sudo user that cannot delete me?

I'm sudoer on a remote linux machine and would like to create another user with the maximum privileges, except the privilege of managing my account. I'm assuming a sudoer can delete or change the ...
2
votes
1answer
238 views

'who' has no output

I'm new to Arch Linux, and I just built my system up. But when I ran who in urxvt, I got nothing. Anyone know what's going on? BTW. I use Slim + OpenBox. And here are parts of my configure files. rc....
2
votes
2answers
176 views

How to create a new user without his own FS but with access to write to only one folder of user that creates him?

What are the command(s) to create a new user (not from su), give him the ability to write to only one folder which is some directory owned by an already existing user (the one that created him)? ...
2
votes
1answer
1k views

Deny external SSH access to a user

Is it possible to deny access to a user (in my case www-data) from outside the network? Or possibly deny this: ssh www-data@example.com But allow this if already logged in: su www-data
3
votes
2answers
1k views

A question about permissions of hierarchical directories

I have some directories, with following permissions: drwxr-xr-x 18 user1 root 4096 Oct 27 11:25 /home/test1/test2 drwxr-xr-x 24 user1 root 4096 Oct 21 08:38 /home/test1 drwxr-xr-x 492 root root 12288 ...
1
vote
1answer
6k views

How to show and modify user info in Ubuntu server?

If I want to put some personal information (like Full Name) to an account, how can I check it again? And how can I modify it? On Ubuntu server. With command line only.
7
votes
4answers
373 views

How can I safely give a shell to somebody?

I have a question about giving a shell account to somebody. How safe is it? He could read /etc. How can I give a secured shell account that will only restrict the user to some bins and his own home? ...
7
votes
2answers
7k views

Why is sudo telling me my password is wrong?

I recently installed OpenBSD 4.9 in my computer, so I could learn a little bit about Unix-like operating systems. I added a new user to the system called bruno. Ok. When I use the 'sudo' command, it ...
5
votes
3answers
533 views

Unix users, groups, and permissions

I don't understand unix users, groups, permissions, etc. For example, things managed by the chmod, chgrp, usermod, groupadd, etc. commands. How do all these things work?
2
votes
1answer
7k views

Changing my default primary GID for every login session

I read the following about newgrp: The newgrp command is used to change the current group ID during a login session. This made me think, how can I change my default's primary group ...
2
votes
2answers
856 views

su user fails with “grep: /var/cpanel/users/user: Permission denied”

I just did something pretty simple. Given a user user, I modified his user id, primary group's id, and added him to a new group in order to make my server use the same uid and gid as another server ...
2
votes
2answers
2k views

Directory/files owned by a non-existent user

A user has created a directory with files, but the user does not exist in /etc/passwd or /etc/group. The system is a Fedora server with an FTP server and proxy which redirects to a CentOS server with ...
2
votes
1answer
87 views

skill on your own session

So I kind of (read: did) run skill -STOP -u <username> on my own session... and I don't have root privileges on the machine. Short of getting the sysadmin to restore things (he's away), is ...
10
votes
2answers
5k views

How to restrict internet access for a particular user on the lan using iptables in Linux

Let's say there are two users on the LAN, A and B. How do I restrict user A from internet access using iptables rules and saving the rules so that after reboot, they are still effective. And suppose I ...
14
votes
2answers
15k views

GID, current, primary, supplementary, effective and real group IDs?

The following links discuss these concepts in different contexts. I have read their definitions, but I still can't tell how they are related, or if some of them are just the same. Current group ID ...
4
votes
1answer
814 views

How to disable certain system calls for a given user?

I am creating a web app similar to codepad and for each run-action my app copies a directory (/home/radeks/voidptr/private/chroot-root) to /tmp/voidptr/[random-id]/chroot-root. This chroot directory ...
2
votes
1answer
1k views

NFS to clients with different uid:s than on the server, where the client uid:s shall not show up in the server

I have a problem with a embedded Linux device that is mounting its root filesystem over NFS. But for different reason the embedded device is a single user device running as root (and later it will ...
4
votes
2answers
1k views

How to see who is logged on to many workstations?

Before I go to work creating my own I would like to find an existing system to do the following: Provide a concise list of users logged on to any of the workstations Show workstation host name, IP, ...
6
votes
1answer
737 views

Backing up and restoring a system user account

How would I go about completely backing up a user account and restoring it on a new system? The Home directory is just 'copy-and-paste'. But then what about things like the account password; and its ...
3
votes
1answer
3k views

User logged in by sftp does not show up in `w`

My server is Centos 5. I have a chroot environment set up with the following in my sshd_config Match group sftponly ForceCommand internal-sftp ChrootDirectory %h AllowTcpForwarding no ...
3
votes
3answers
705 views

Group information reported wrong for a specific user

I have a problem on a server I manage. An account (specifically, my account) does not seem to have the correct groups. I think the problem is most easily demonstrated by looking at the following ...
2
votes
1answer
136 views

Suddenly changing users [closed]

Has anyone ever encountered a scenario where you are logged into a system going about your standard business, cat, ls, tail, grep, vim, find etc. and suddenly permissions to regular things stop ...
9
votes
3answers
16k views

Correct permissions for /var/www/html?

I'm able to write changes in the home directory, but when it comes to the /var/www/html folder, it's not allowing me to make any changes or create new files or folders. I'm able to view the files in ...
3
votes
2answers
8k views

How can I have a separate umask for directory or user?

I want a separate umask for a directory or a user. How can I do this? Edit: I am using Debian 6. The reason why I want to do this is, I want all my SFTP users to create files with write on group. ...
5
votes
4answers
1k views

How sudo/root-ness detection works

Programs that make changes system-wide require sudo unless I am already the root user. Now, the question is: how exactly does the system figure out that I am (not) root? Does it: Check to see if I'...
3
votes
1answer
287 views

Duplicate a user, or at least the password

I have some application that needs to create users that have the same password as others. Is there a way to do this without having to edit the /etc/shadow manually? Some sort of command?
2
votes
1answer
372 views

Verify that /etc/passwd has correct number of fields on each line?

I'm looking for an easy, portable way to validate the number of fields in /etc/passwd, /etc/shadow, /etc/group and /etc/master.passwd. This would run on FreeBSD, Linux and other Un*xes. pwck does this,...
4
votes
1answer
654 views

Why do I need to use newgrp or su (or logout and login again) to have new group memberships applied?

What is it that makes new group membership require a new login (or new login shell as started by su or newgrp) to be visible? Just running another bash (or whatever other shell) instance with --login ...
9
votes
1answer
11k views

Mounting an ext3 fs with user privledges

I'm trying to mount an ext3 file system from another linux installation so that the user, not root, will have full access to all the files. (I really do need user to have access to those files, ...
3
votes
3answers
4k views

Reset all groups to default

I recently set up some groups and users on my machine, and now I want to remove all those users and all those groups. Somewhat stupidly, I read on an Ubuntu forum or something like that that it was ...
2
votes
2answers
307 views

using chown in linux

I want to assign www-data user full rights in folder /var/www/ and all of the files inside this folder. I have tried chown www-data /var/www/
11
votes
3answers
5k views

What is the point of the 'operator' user?

Many un*x systems ship with a user account named 'operator'. What is the purpose of this account? Do some systems actually make use of this account, or is this more of a historical legacy? Have you ...
3
votes
4answers
2k views

different shell for root and non-root user

When I ssh as root, my shell is bash, but when it's a non-root user it is sh. How can I make them both to use bash? This actually goes against the logic in this question: Why root's default shell is ...
1
vote
1answer
68 views

Equivalent of newusers for groups

The newusers command is useful for adding or modifying users in bulk. Is there an equivalent command for managing groups?
9
votes
2answers
8k views

What are the allowed group names for groupadd?

I followed these instructions to build Shadow, which provides the groupadd command. I am now getting an error when trying this: $ groupadd automake1.10 groupadd: 'automake1.10' is not a valid group ...
6
votes
1answer
2k views

How to get the name of the user that launched `sudo`

My problem: I have a Python program, and the user launch it using sudo. Sometimes I have to get the user's home, and I can do this only knowing its name: import pwd pwd.getpwnam(username) So: how ...
3
votes
2answers
8k views

How can I switch one user to another in Freebsd?

How can I switch one user to another in Freebsd? For examples, I am user david now and I want to change to user Bob. This is a personal OS for my study. not a server. I searched it, but only got ...
5
votes
1answer
7k views

What is hvc0? (appearing in “who” list)

I have an Ubuntu Server, and when I type who, to see who's connected, I can see that there's a user connected, and instead of being logged to a pts/x, he's connected to hvc0. Is there something to ...
11
votes
7answers
3k views

Is it bad practice to set root's shell to something other than the default?

Once a friend of mine (who is an experienced Unix/Linux user) told me that setting root's shell to something other than sh (i.e bash or zsh) might create problems, because some script might assume ...
4
votes
3answers
4k views

How to find the machine from which a user logged into current machine using ssh?

In a multi server architecture, is it possible to find out from which machine a user logged into current machine using ssh? For example, user1 logged into host1. From there, the user logged into ...
7
votes
1answer
1k views

Why root's default shell is configured differently with other normal user account's default shell?

As I know, root's default shell is configured csh and normal user's default shell is sh in FreeBSD. And in Ubuntu, root is dash, normal user is bash. (refer: What's the Ubuntu's default shell?) Why ...
2
votes
1answer
5k views

How do I add a new user to an embedded Linux system by hand?

I have a system which was designed for use by root only and I want to run an FTP server on it. The software I use handles authentication by using same username and password as OS itself. To me it ...