Short for "file system permissions" - access control based on user, group, or global access.
40
votes
4answers
20k views
How do I sudo a command in a script without being asked for a password?
I want to turn my system on automatically every day. So I use the below code in my Python script, but sudo asks me for a password every time:
os.system('sudo sh -c "echo date \'+%s\' -d \'+ \
...
33
votes
7answers
22k views
How do I install Sublime Text 2?
I installed Sublime Text 2 on 12.04 as per this tutorial.
However I don't have adequate permissions when launching the program from the Unity launcher. For example I cannot install packages, or if I ...
30
votes
7answers
19k views
How to 'chmod' on an NTFS ( or FAT32 ) partition?
I have a script that I need to execute on an NTFS partition. The script's permission is set to 600.
I attempted to modify the permissions by running chmod 755 script.sh, which doesn't report a ...
30
votes
2answers
9k views
How do I change my username?
Some time ago when I installed Ubuntu I chose a rather stupid username for my account that I do not want to use anymore.
How do I change this (including the name of my home directory) without ...
29
votes
2answers
8k views
Why should /var/www not have chmod 777
When opening a page from my server, I sometimes get a "Permission denied" error which I can solve by running chmod -R 777 /var/www. However, people are telling me that this is a bad idea for security ...
28
votes
7answers
37k views
Whats the simplest way to edit and add files to “/var/www”?
Having installed the web server is there a simple way to set a user able to use the graphic interface to copy files and directories to the local web server /var/www
I gave myself administrative ...
26
votes
6answers
98k views
Change folder permissions and ownership
I would like the user to have full rights on this folder (as well as all sub-directories and files in it):
~/.blabla
currently owned by root.
I have found numerous posts (in this forum and ...
26
votes
2answers
10k views
What is “umask” and how does it work?
I believe that umask is something that controls file permissions, but do not fully understand it.
After running umask 0644 in a terminal, I cannot read the files I create with the command-line text ...
25
votes
5answers
34k views
How do I add a user to the “sudo” group?
In /etc/sudoers I see this:
# Allow members of group sudo to execute any command after they have
# provided their password
# (Note that later entries override this, so you might need to move
# it ...
25
votes
4answers
6k views
What is the difference between the 'sudo' and 'admin' group?
I noticed that two groups are granted similar-looking permissions in /etc/sudoers:
# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL
# Allow members of group sudo to execute ...
21
votes
4answers
639 views
When using sudo with redirection, I get 'permission denied'
When using sudo to allow edits to files, I regularly get 'permission denied'.
For example, my mouse is jittery and sluggish, so I want to disable polling:
sudo echo "options drm_kms_helper ...
18
votes
3answers
5k views
How can I get octal file permissions from command line?
There is a chmod command to set file permissions, but can I get file permissions in octal mode (such as 755) from the command line?
17
votes
3answers
506 views
When are “User Privileges” relevant?
I notice that many of the user privileges in "Users and Groups" are not ticked on my user, but I still have access to the items they specify. For example, I'm constantly using VirtualBox for ...
16
votes
3answers
11k views
sudo: unable to resolve host (none)
I have this issue on AWS on some servers. Whenever I run sudo the terminal is stuck doing seemingly nothing, until it finally spits out this error message. My terminal looks like this:
...
16
votes
7answers
22k views
How do I get permissions to edit system configuration files?
I can't seem to edit and save config files in the root system (eg: /etc/dhcp/dhcpd.config); it just says "permission denied" or the save option is blocked in the text editor.
I'm pretty sure I'm a ...
13
votes
2answers
2k views
How do file permissions work?
Can you explain briefly the main concepts and command line tools used to manage file permissions?
13
votes
4answers
517 views
Good and easy way to share files on local machine
I would like to have a directory that has following properties:
Many users can copy files into it
These files can be deleted/changed by these users (user A can delete/modify file that was copied ...
13
votes
1answer
217 views
How Will App Permissions be Handled in Ubuntu Touch?
Most elements of the hardware, or data sets shared between apps on the Android and iOS platform are controlled strongly, and only provided to apps explicitly on a need-to-know basis. This can allow ...
12
votes
4answers
608 views
Is it possible to make a file that has full permissions for everybody but is impossible to delete?
Without using sudo, preferably?
12
votes
2answers
585 views
How can I rename items in places I don't own, like / , and why shouldn't I?
I get a Permission denied message when trying to rename files and folders in places like /, /usr, and other people's home directories. I'm an administrator. How can I do this?
Also, I've heard that ...
11
votes
3answers
22k views
'chmod u+x' versus 'chmod +x'
What is the difference between chmod u+x and just chmod +x? I have seen a ton of tutorials that say to use u+x to make scripts executable. However, the u is not mentioned in the chmod help or ...
11
votes
2answers
773 views
Is it a bad idea to run SELinux and AppArmor at the same time?
My corporate policy says that Linux boxes must be secured with SELinux (so that a security auditor can check the 'yes, we're extremely secure!' checkbox for each server). I had hoped to take ...
11
votes
8answers
9k views
How to run an Application as another user?
I use krusader for file management stuff. the problem is that apache's DocumentRoot should be under chown www-data:www-data /path/to/www. so using krusader (which is run under my account) I've not ...
11
votes
2answers
2k views
What do the groups do in “Users and Groups”?
I know that some define permissions on the file system (such as www-data). But I don't understand why this question was answered successfully by adding a user to the "Video" group.
So the question ...
10
votes
4answers
4k views
Why can other users see the files in my home folder?
I just added a new, underprivileged "desktop user," and I was surprised to discover that it can see the files in my home folder.
What is the rational for setting up such lax permissions?
10
votes
2answers
226 views
How can I preserve the executable bit on a file that is synchronized by Ubuntu One?
A script I am working on is in a folder that is synchronized by Ubuntu One. Every time I edit it from another computer, it looses its executable bit and I must manually reapply chmod +x.
How can I ...
10
votes
8answers
609 views
How can I make a write-only view of a folder?
I want to have a place on the filesystem that presents a write-only "view" of another folder that I have read-write access to.
I'm picturing something that's similar in behavior to an FTP drop box, ...
10
votes
4answers
1k views
Hide 'Your profile could not be opened correctly'
I have a small public internet cafe, with Ubuntu 10.04 and 10.10. I'm using
Google Chrome 7.0.517.44 (64615), with AutoScroll - Version: 2.7.5; AdBlock is removed because of high CPU loads, and ...
9
votes
3answers
4k views
How to mark “allow executing file as program” on an external drive
If I try to set this option for a file on an external drive it just unmarks itself. Doing chmod +x has no effect. The drive is mounted with default options.
9
votes
3answers
52k views
How do I install .run files?
My PC has both Ubuntu and Windows 7 installed. I have installed all my drivers in Windows like NVidia graphics, motherboard etc. Shall I install them in Ubuntu too?
I looked on the web for my Nvidia ...
9
votes
4answers
4k views
.exe file permission fail
I'm trying to run a exe file that is located on my Vista partition, when I browse to the file and try to change the file to run as executable the tick box unticks itself right after i tick it, i tried ...
9
votes
4answers
10k views
Change owner of internal hard drive partition from root to user
I have a number of drives internal and external. Some are partitioned. Most mount automatically at boot (all did at one point).
One partition is owned by root and therefore does not mount ...
9
votes
1answer
9k views
Correct way of mounting a Windows share
I mounted a Windows share to my Ubuntu 11.10 system via adding the following line to the /etc/fstab:
//serveraddr/sharedfolder /mnt/foldername/ smbfs credentials=/home/myname/.smbpasswd 0 0
using ...
9
votes
4answers
4k views
How can I run an executable from a CD when it doesn't have the executable bit set?
A textbook I'm using came with a CD containing a few supplementary applications. To my pleasant surprise, it appears to include an installer for Linux.
The readme file on the CD provides the ...
9
votes
1answer
614 views
How can I become the owner of a file that origins from another pc / user?
I have a file from another pc with ubuntu, the owner of the file is my user account from this pc. How do I change the owner to my useraccount on another pc so that I can use it?
When i try to change ...
9
votes
1answer
7k views
Can see samba shares but not access them
For the life of me I cannot figure this one out.
I have samba installed and set up on the ubuntu box and on the Win7 box I CAN SEE all the shares I created.
I created two users on ubuntu that map ...
8
votes
1answer
8k views
Minecraft jar not marked as executable
I looked up several tutorials on how to install and they dont work. I do everything correctly but then i get this:
The file
'/home/mike/Downloads/minecraft.jar'
is not marked as executable. ...
8
votes
3answers
450 views
Why doesn't `sudo cd /var/named` work?
I want to cd into /var/named but it gives me a permission denied error, and when I want to use sudo to do this I am not permitted. What is the technical reason for this, and is it possible to do this ...
8
votes
4answers
10k views
How can I recursively change the permissions of files and directories?
I have ubuntu installed on my local computer with apache / php / mysql.
I now have a directory at /var/www - inside which I have several of my ongoing projects. I also work with opensource ( drupal, ...
8
votes
2answers
40k views
How to copy files into /usr/local/? (permission denied)
I'm still a little new to Ubuntu and was wondering how I can copy files, in this case Aptana Studio, to /usr/local/ without being denied.
Is there a way to do it in terminal? Or a way to allow ...
8
votes
3answers
10k views
Can't set permissions for files on an NTFS partition
I remember that I was able to run a Linux .exe that was placed on an NTFS partition earlier before I installed 10.10 RC. But if I try to run it now, I can't run it as it hasn't the execution ...
8
votes
3answers
15k views
Read Only usb stick that won't let me do anything to it
Somehow I messed up and accidentally made my usb stick into a read only file system. I have tried a bunch of things to delete the files, including the basic (rm -f myfile) and attempting to allow ...
8
votes
1answer
4k views
What user settings control audio access?
Running a regularly updated 10.04 LTS we have a weird issue with access to audio with pulseaudio 0.9.22. Sound device is ATI Technologies Inc SBx00 Azalia (Intel HDA)
Login user1 after reboot: sound ...
8
votes
2answers
10k views
Backup files with rsync: error 23
I'm trying to make a backup of my /home to transfer all data from one computer to another. I wanted to save the backup on the same computer and than transfere it to another one. For safety reasons, ...
7
votes
4answers
1k views
What if I accidently run command chmod
I accidently ran
sudo chmod 755 -R /
instead of
sudo chmod 755 -R ./
I stopped it after few seconds, but now there is some problems such as
sudo: must be setuid root
How can I revert ...
7
votes
3answers
2k views
How to move files into /usr/bin in Nautilus without getting permission errors
I'm trying to move some files into /usr/bin in Nautilus but I'm getting permission errors. I know I can do it via the terminal using sudo but how can I do it in Nautilus? I would expect it to popup a ...
7
votes
4answers
8k views
Apache symlinked to home directory - Permission Errors
im having a few problems symlinking my /var/www/ to a new Webroot directory inside my home folder. I think these stem from my lack of understanding of linux permissions.
As far as im aware, symlinks ...
7
votes
4answers
13k views
Mount NTFS partition at startup, with non-root user as owner
I'm currently mounting an NTFS partition at startup using the following line in /etc/fstab:
/dev/sda3 /media/data ntfs nls=iso8859-1,umask=000
To my Ubuntu 11.10 installation, ...
7
votes
2answers
5k views
Changing permissions on serial port
I'm using the Arduino IDE in Ubuntu, and am having issues with the serial port. It has worked in the past, but for reasons that may be unnecesary, I felt the need to change the ownership of some of ...
7
votes
4answers
2k views
Mounting NTFS as read-only
My PC have 3 NTFS partitions (main and backups) plus Ubuntu on dual boot. I want to keep NTFS partitions available, but mounted as read-only by default, so that other users (and accidentally even me) ...
