All about Unix groups and access control.

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2answers
32 views

What is the significance of the “wheel” group? [duplicate]

I've commonly seen references to a wheel user group online as well as when setting up my sudoers file. Does naming a group wheel imply something special about the group or is it just a name for a ...
11
votes
4answers
608 views

Groups differ from the local ones when logging in remotely

We store our users in LDAP, alongside some groups that have meaning across different systems (organizational roles including wheel). There are also groups local to workstations, e.g. audio or video ...
3
votes
1answer
16 views

Why does uucp take group 10?

According to YoLinux, group ID 10 typically belongs to wheel. And on my Arch Linux installation, sure enough there in /etc/group is wheel:10. However, on my Ubuntu machine instead I'm greeted with ...
2
votes
1answer
369 views

Adding Windows user to Linux group; possible?

I have a NAS that runs on Linux and I connect to it from my Windows desktop. I noticed that all directory in that drive belongs to user 'root' and group 'root'. That effectively denies me the right to ...
3
votes
3answers
103 views

Why only one active group at a time?

As far as I understand the users in Unix system can belong to multiple groups and one of them will become the primary group for that user. Others will be supplementary groups. All of this User/Group ...
1
vote
2answers
25 views

Where is core group defined on coreos?

On CoreOS EC2 instance, I find the following: $ cat /etc/passwd root:x:0:0:root:/root:/bin/bash core:x:500:500:CoreOS Admin:/home/core:/bin/bash $ cat /etc/group wheel:x:10:root,core sudo:x:150: ...
0
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1answer
20 views

How to change primary group? [duplicate]

I have a user like this: uid=501(ironsand) gid=500(foo) groups=500(foo),10(wheel),497(git),501(ironsand) And to change primary group to ironsand like gid=501(ironsand), I typed this command: sudo ...
3
votes
3answers
6k views

What does GID mean?

What does GID actually mean? I have Googled it and this is what linux.about.com said: Group identification number for the process. Valid group numbers are given in /etc/group, and in the ...
2
votes
2answers
707 views

group option in fstab not working

I'm trying to take advantage of the "group" option for fstab entries and not having any success. From the mount man page: Normally, only the superuser can mount filesystems. However, when fstab ...
1
vote
1answer
42 views

Groups in the Samba configuration

I can't quite understand groups. For example, lets say if I add the following into my samba config: valid users = @users Must the group users exist on my system or is a samba group itself? And if ...
2
votes
1answer
80 views

id command doesn't show all user's groups [duplicate]

I did a usermod to add the current user user in a group, but when I run id -Gn it only shows the main user's group: [user@computer ~]$ id -Gn user But when I specify the user, it works normally: ...
1
vote
1answer
67 views

how to make logstash read kannel log

I got logstash installed on ubuntu 12.04 using the apt repository. But logstash is not reading any document. In logstash log there are teh following: ...
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2answers
34 views

how to determine the permissions of groups?

When you invoke sudo, it prompts for password and then checks the /etc/sudoers configuration file to see if the user is permitted access to run the command. /etc/sudoers is the sudo configuration ...
1
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0answers
54 views

Which command would you use if you want to remove the password assigned to a group

Suppose I have one or more groups (as in the user database as backed by /etc/group or LDAP or NIS+...) configured with a password (for the sg or newgrp commands). Which command would you use to ...
3
votes
3answers
54 views

Is it possible to have a bashrc for a usergroup?

Is it possible to execute some bashrc file for all users in a group? If you can do that system-wide in /etc/profile then why not for a usergroup?
0
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1answer
22 views

As what user does a command end up executing? [duplicate]

How can I find out as what user a command executes? (I'm running Ubuntu, but I suspect the answer applies to Unix in general). What I'm trying to do is get msmtp running and logging to ...
-1
votes
1answer
26 views

add groups from external file

I want to write a script which add groups to the system, specified in groups.txt file. content of groups.txt : group01 : computer group02 : electronics group03 : IT . ...
3
votes
1answer
100 views

groupadd failure while writing changes to /etc/group

I have been following this guide on installing debian-kit on my Sony Xperia Tablet Z and the installation goes fine until I try to apt-get install andromize which fails with the error groupadd: ...
3
votes
2answers
114 views

Short, simple command to create a group if it doesn't already exist?

What is the cleanest way to modify this command in bash to only run if the group does not exist? groupadd somegroupname A one-liner would be best.
2
votes
3answers
79 views

adding list of users to multiple groups

I have a shell script which add list of users which is listed in another file lets say users.txt. After that, I want my script to add users to multiple existing groups with condition, one user may ...
2
votes
3answers
1k views

Limited SSH user on Ubuntu 12

I'm running Minecraft on a server. How can I give my friend SSH access just to the minecraft folder (a root folder), the screen command, and some ports?
1
vote
1answer
28 views

Troubleshooting joining a group in Mint in VirtualBox [duplicate]

I am trying to join my user to the vboxsf group to access a VirtualBox shared folder from inside my Linux Mint virtual machine. However I'm encountering a problem that I can't troubleshoot. I've ...
6
votes
2answers
5k views

I added a user to a group, but group permissions on files still have no effect

I changed permissions of a file (chmod g+w testfile) and running ls -l testfile gives: -rwxrwxr-x 1 user1 user1 0 2011-01-24 20:36 testfile I then added a user to that group ("/etc/group" has ...
0
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1answer
29 views

Cannot lock group file: already locked

I'm trying to add a group using this command: groupadd somegroup which returns: Cannot lock group file: already locked. I did some research and most of the solutions require removing a lock file ...
4
votes
1answer
132 views

View List of Sudoers with No Sudo Priviledges

If I'm not a sudoer, is it possible to view the list sudoers? Does /etc/group show this information?
1
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1answer
85 views

AT&T UNIX System V Release 4 - How do I create a new “Administrator” user?

I am running AT&T UNIX System V Release 4 Version 2.1 inside VirtualBox, and want to create a new "user account" for myself. At first, I simply created a new user with the useradd command, but ...
1
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3answers
99 views

Delete non-unique group with group ID as primary group of a user

So say I have two groups with names testing1 and testing2. Both groups have the same group ID of 2000. Then I add a user named testing-user with GID of 2000. Along the way I want to delete group ...
59
votes
5answers
81k views

How do I remove a user from a group?

Which command should I use to remove a user from a group in Debian? When adding a user to a group, it can be done with: usermod -a -G group user However, I could not find a similar command ...
7
votes
4answers
176 views

Groupwise uniq command?

I am searching for a command to get from a file in this format: hello 32 hello 67 hi 2 ho 1212 ho 1390 ho 3000 To this format (deduplicate by taking the last row of a "group"): hello ...
2
votes
3answers
279 views

User permissions problem Linux

Every time I create a new file from "eclipse", I need to run these two lines of code to get the r/w permission: chmod -R 775 /var/www/folder/filename.extension And/Or sudo chown -R ...
11
votes
3answers
28k views

Change gid of a specific group

I'd like to change group id of a specific group. There are so may solution for changing the gid of a file or directories. But that's not what I want. Is there a way to do that?
74
votes
6answers
22k views

Where did the “wheel” group get its name?

The wheel group on *nix computers typically refers to the group with some sort of root-like access. I've heard that on some *nixes it's the group of users with the right to run su, but on Linux that ...
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votes
2answers
41 views

Clarification on permissions with GID & UID in UNIX

If Test1 & Test2 are users, then Test1 : UID : 501, GID :501, groups=501,100 Test2 : UID : 502, GID :502, groups=502,100 What will be the correct option from below and explain how? Test1 ...
0
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2answers
333 views

Privileges for jenkins at apache's folder

I'm having issue similar to this: How to copy files as Jenkins "post build" action if i don't have privileges to destination directory I'm willing to move/copy/rsync files from jenkins ...
1
vote
0answers
79 views

postfix expand ldap group AND afterwards resolve alias

We have a postfix server which has the user config stored in a openldap directory. Recently we also implemented ldap groups which are expanded by postfix. This works fine, unless the group expands to ...
3
votes
1answer
70 views

Two users with different permissions on same directory

Is it possible to give two users different permissions on the same directory? I want to use it for ftp: userFull gets R+W and userLim gets only Read, depending on who logs on. Im getting stuck on the ...
3
votes
2answers
104 views

/etc files on a different partition

My setup requires that some of my /etc files reside on a separate partition. For this purpose I've created a softlink: ls -li /etc/group 956 lrwxrwxrwx 1 root root 21 May 7 15:48 /etc/group -> ...
2
votes
2answers
42 views

Who should own files shared by a group and where should they go

I am configuring a Linux work station that will be used by a small number of users (20-30). These users will belong to a small set of groups (5-10) with each user belonging to at least one group and ...
2
votes
1answer
100 views

Can one directory be owned by two groups?

Can one directory be owned by two groups (RHEL 6.2)? I have created one directory: mkdir /opt/shared, then I created two groups: groupadd sales groupadd marketing I added manually to each of ...
1
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2answers
32 views

Store a file for all users within a group

If user A is member of group foo, is it then possible for A to share a file for all members within foo without root permissions? chown foo:foo file Is not permitted without privileges. A can say ...
5
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2answers
1k views

Getting new files to inherit group permissions on Linux

I am having a problem with permissions on a Linux server. I am used to BSD. When a directory is owned by a group the user who owns it isn't in such as www-data, files created in it will be owned by ...
4
votes
1answer
68 views

How do you give a developer group access to apache, MySQL, php and the webroot?

We have 3 web designers that are currently logging in to our server via root to configure apache and setup websites. I have very basic linux knowledge (I'm a web designer) and have created users and ...
5
votes
1answer
256 views

Apache, Group Permissions and User Uploads

I have a folder named "digitalgoods" with the following ownership -- apache:apache residing outside of the htdocs folder and is therefore not accessible to the public. However I need the same folder ...
1
vote
2answers
54 views

Command to know privileges of a user group

If I run cat /etc/group command or groups username I am able to know the list of groups as group of a particular user. Is there any command through which I could know which type of privileges a ...
7
votes
1answer
487 views

Why cannot a user change group ownership of his own files? [duplicate]

Why cannot a user change the group permissions of files which he owns. Let's suppose I have user martin: $ ls -lAd /home/martin/ drwx------ 8 martin martin 4096 Apr 20 01:06 /home/martin/ For some ...
1
vote
1answer
84 views

Re-add accidently deleted system group

In my attempt to delete the admin user group I accidentally deleted the adm system group. I "added it back" by issuing addgroup --system adm. I have a feeling this is going to bite me back later. Is ...
11
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2answers
335 views

Why is root in wheel and operator? Can root being in a group ever make a difference?

I just noticed on my FreeBSD machine that root is in wheel and operator. I'm trying to think of a situation where UID 0 being in a group would have any effect on... well... anything, and I'm coming up ...
0
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1answer
32 views

Trying to change GID on AIX server

I am trying to change GID on Unix server "AIX". I want to change mygroupname:!:79002: from group GID from 79002 to 79003. I have permission to use sudo /usr/bin/chgroup. I have tried everything, ...
3
votes
2answers
55 views

Why are newly created users assigned to primary groups of their usernames?

I've noticed that on a number of linux distributions that whenever a new user is created, it is assigned to a primary group of its own name. eg. If i create a user called "testuser", by default it is ...
0
votes
1answer
89 views

How can I allow a group to execute a command as another user?

I'm conservative about my sudoers policy. I'm trying to allow wheel users to run psql postgres postgres as the postgres user (because when ident that's the only way it works). root ALL=(ALL) ALL ...