Permissions are the unix way of controlling access to resources such as files, directories and devices and may be specified for an owner, group, or all users.

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How do I give all the permissions to a file for a single user that's not me?

When I want to grant access to another user to my file, I use chmod 777 file, but if I want to be sure I'm granting permission just for that user, how can I do it? -- update The file is owned by ...
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2answers
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Why do I get an “rsync: failed to set times on … : Operation not permitted (1)” error on Ubuntu 10.10 with SME Server 7.4? [duplicate]

I am trying to cron an rsync via ssh between two fileservers that are running SME Server 7.4 and Ubuntu 10.10, respectively. The first rsync worked just fine (for reasons that I do not know), but now, ...
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2answers
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Why can't root on one machine change nfs mounted content from another machine?

On my NFS server, I have the following export defined: #NFS exports Database /shared -alldirs -network=192.168.1 -mask=255.255.255.0 On my NFS client: 192.168.1.7:/shared /shared nfs rw 0 0 ...
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5answers
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Is there a web based converter between rwx and the octal version?

I can never remember what the conversion is from something like rw-r--r-- to 644. Is there a simple web based converter between the 2?
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3answers
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Why is file ownership inconsistent between two systems mounting the same NFS share?

I have one IBM AIX server (serverA) which is connected to the san storage. I have created a volume group and also file system (jfs2) and mounted to directory /profit. After that I created a NFS ...
4
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3answers
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Permissions issues for shared directory on a server

The setup is we have a VPS running Debian Squeeze, and I've set up a shared directory for us to share files. So far I've followed this guide: ...
5
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2answers
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Permissions: What's the right way to give Apache more user permissions?

Context: I am making an in-browser control panel that gives me one button access to a library of scripts (.sh and .php) that I've written to process various kinds of data for a project. It's a "one ...
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2answers
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What directories/file permissions should i ensure are set?

I have a similar question about default software configuration. For this question i would like to ask What directories/file permissions should i ensure are set? Aprrently Is it normal to get ...
4
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5answers
841 views

debian security /etc permissions

I'm setting up a debian box with shared webhhosts. These users don't have ssh permissions, just ftp. The users are allowed to use PHP and I setup suphp for that so the php processes runs under their ...
6
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1answer
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I can't remove a directory tree with rm -rf

This seems very strange to me. I'm running kernel 2.6.37.2 and ran: ~]$ cp -r /proc/ here ~]$ rm -rf here I get some permission denies when copying as expected and I eventually hit Control-C. I get ...
4
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3answers
284 views

Give a warning when something is about to be deleted (by root)

I know that root can do anything, but is there a way to at least alert root that they are about to delete a folder that perhaps shouldn't be deleted? We keep a work directory in our /tmp folder, and ...
3
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1answer
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Default File Permissions - Ubuntu & VSFTPD

I have a server setup with Ubuntu, Apache2 and VSFTPD. We virtual host several sites on this machine. Typically, I use the same process to set up the new sites, but the default permissions for some ...
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2answers
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I can't delete a file that I have write permissions for as a group member

$ touch testfile $ chmod g+w testfile $ sudo adduser user2 user1 $ stat -c'%a %A' testfile 664 -rw-rw-r-- $ su user2 Password: $ groups user2 user1 $ rm testfile rm: cannot remove `testfile': ...
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vote
3answers
205 views

How to make files created by a specific user to have specific permissions by default

Here's a sequence of commands and the resulting output: $ touch testfile $ stat -c'%a %A' testfile 644 -rw-r--r-- What must I do so that when a user follows that sequence, I get this output ...
3
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1answer
681 views

Set visible directories for SFTP access?

I am setting up SFTP access to one of my machines running Linux with the Dropbear SSH server. When I SFTP onto the machine remotely, I can see the entire filesystem on it, even if I might not have ...
75
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2answers
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Why do we use su - and not just su?

I don't understand why su - is preferred over su to login as root.
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4answers
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sudo permission denied but su grants permission

this is the first occurrence where su was required for me. I read an article about changing the value in /sys/devices/virtual/backlight/acpi_video0/brightness to alter my laptop's screen brightness. ...
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1answer
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`chmod 770 folderName` restrics access to subdirectories & subfiles?

If I run chmod 770 ./folderName, then users who are not the owner or in the group owning ./folderName (i.e. users in the “others” category) cannot access ./folderName/folderB or ./folderName/fileC, ...
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5answers
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How to run part of a script with reduced privileges?

I have the following problem: On every machine running Postgresql there is a special user postgres. This user has administrative access to the database server. Now I want to write a Bash script that ...
15
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3answers
4k views

How to “jail” a process without being root?

Were I root, I could simply create a dummy user/group, set file permissions accordingly and execute the process as that user. However I am not, so is there any way to achieve this without being root?
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2answers
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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 ...
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4answers
283 views

Backup script permission issue

I have a server with a user named deploy-user and have written a backup script to backup a number of websites associated with this user. However one of the sites I'm trying to backup has a directory ...
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5answers
2k views

How do I recursively check permissions in reverse?

There's a command, I think it comes with apache, or is somehow related to it, that checks permissions, all the way down. So if I have /home/foo/bar/baz it will tell me what the permissions are for ...
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2answers
682 views

HPUX setacl leaves uid behind

I have a shell script that I execute after uninstalling a web application. The script is meant to clean up permissions that were needed during the execution of the application. find /opt/path -exec ...
3
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1answer
464 views

Permissions issues with mounting remote server into a specific folder

I'm doing the following to mount a remote server to a specific path on my server: sshfs user@remoteserver.com:/backup/folder/ /home/myuser/server-backups/ However when I mount the server the folder ...
9
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1answer
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How to (safely) move /tmp to a different volume?

Today the /tmp directory filled up on a machine at work. The problem was, it was on the root partition which wasn't very big. In order to fix this, a co-worker created a /new/tmp directory elsewhere, ...
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3answers
477 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?
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1answer
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simultaneously share /dev/videoX with multiple applications?

the goal is to use the same webcam for video chat apps and for home security at the same time. Currently, the webcam is working just fine with either VLC (or mjpg-streamer) and with Kopete - just not ...
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1answer
515 views

svn and webserver files ownerships

I've an issue with files ownerships. I have a drupal website and the "files" folder needs to be owned by "www-data" in order to let the users to upload files with php. However I'm now using svn and ...
2
votes
1answer
636 views

How to assign correct permissions to both webserver and svn?

I've an issue with files ownerships in unix. I have a drupal website and the "files" folder needs to be owned by "www-data" in order to let the users to upload files with php. However I'm now using ...
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2answers
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How to insert text into a root-owned file using sudo? [duplicate]

Possible Duplicate: Redirecting stdout to a file you don't have write permission on Running a command like sudo echo 'text' >> /file.txt fails with: bash: /file.txt: Permission ...
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2answers
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How is file ownership affected across different systems?

As I understand Unix file systems, any file on a unix system must belong to a group and a user of the said system. A file cannot belong to a group or user that does not exist on the system. From that ...
2
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1answer
613 views

immutable-like flag for perms

Is there any chattr flag that would allow me to lock a file's unix permissons, and not change them without resetting the flag? The file itself should still be modifiable, I just want to prevent ... ...
3
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1answer
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what does the “a” in chattr +ia do?

what does the a in chattr +ia <filename> do? and why would you add the a in combination with the i? note: I know the i is for immutable
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1answer
231 views

What's the best way to configure shared filesystem directories? (beyond standard unix perms)

I have multiple users on my system. I'd like to have shared directories like music, video. pictures etc. The problems is that I want users to be able to write any new files to any directory, but not ...
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2answers
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How to get a program running with root privileges without using su or sudo

I have a bash script that needs to run with root privileges, but must be invoked by the normal user. Difficult part is that the script should not ask for a password, and I don't want to use the ...
2
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2answers
418 views

Unix executable file permission vs runtime user's permissions

I have heard that it is good practice to run an executable as a user with a completely different privilege set than the owner of the task. In fact I heard that it is best to run it as a different user ...
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2answers
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How are file permissions calculated?

Using chmod I could set the permissions for a file, but if the parent ( .. ) directory had conflicting permissions, what would happen? And if I create a new file, using touch or something similiar, ...
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5answers
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How to create a file even root user can't delete it

How to create a file even root user can't delete it ?
6
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1answer
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how to view a directory's permission

What is the command with which you can directly view the permission bits of a directory?
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4answers
1k views

How do I force the user to become root

I have written a bash script for use on my ubuntu box. Now I would like to prevent running this script under my own user and only able to run it as root (sudo). Is there a possibility to force this. ...
4
votes
5answers
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Create directory in /var/run/ at startup

I'm using apache2 and postgres running on Ubuntu Server 10.04. I have removed the startup scripts for both of these apps and I'm using supervisor to monitor and control them. The problem I have run ...
10
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1answer
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Permission bits not being enforced on samba share

I have a problem where permission bits are not being enforced on a samba share using a Linux client. I have samba configured on the server to force a certain user, group and permission bits and this ...
43
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5answers
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Redirecting stdout to a file you don't have write permission on

When you attempt to modify a file without having write permissions on it, you get an error: > touch /tmp/foo && sudo chown root /tmp/foo > echo test > /tmp/foo zsh: permission ...
14
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3answers
2k views

I accidentally chmod -R +x on a directory. How do I restore the correct permissions?

Well, to be specific, it was chmod -R 755. Now every file is executable, which I don't want. I am thinking that I should look at the first two bytes of each file for the #!, but will this cover ...
73
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1answer
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How to set default file permissions for all folders/files in a directory?

I want to set a folder such that anything created within it (directories, files) inherit default permissions and group. Lets call the group "media". And also, the folders/files created within the ...
5
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2answers
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What files in /var need to have specific owners?

I accidentally wreaked unknown amounts of havoc on my web server by running sudo chown -R myuser:mygroup * .* in /var/www, not remembering that .* would include the parent directory (as ..). I ...
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3answers
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How to make a folder private?

I'm using Ubuntu with several users and I want to make folders viewable just for a specific user. Any idea how to do it?
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4answers
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Downsides of umask 077?

What are the cons, for having a restrictive umask of 077? A lot of distros (I believe all, except Red Hat? ) have a default umask of 022, configured in /etc/profile. This seems way too insecure for a ...
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2answers
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How to set up file permissions/ownership for FTP/Apache/PHP on CentOS

I have basic understanding of chmod and CentOS file permissions. 777 stands for 111111111 and rwx for each root, group, user, etc. What I can't get my head around is setting up Apache, FTP and PHP to ...