In computing, permissions (often called "privileges," "access rights" or just "rights") are rules associated with objects on a computer or network. Permissions determine which objects can access which objects, and to what extent.

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Why is “chmod -R 777 /” destructive?

This is a Canonical Question about File Permission and Why 777 is "destructive". I'm not asking how to fix this problem, as there are a ton of references of that already on Server Fault ...
179
votes
5answers
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What permissions should my website files/folders have on a Linux webserver?

This is a Canonical Question about File Permissions on a Linux web server. I have a Linux web server running Apache2 that hosts several websites. Each website has its own folder in /var/www/. ...
137
votes
8answers
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How do I share a Git repository with multiple users on a machine?

I have a Git repository on a staging server which multiple developers need to be able to pull to. git-init seems to have a flag very close to what I'm looking for: --shared, except I'd like multiple ...
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votes
14answers
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What's wrong with always being root?

I have a feeling this is a stupid question, but this is something I've wondered for awhile. I have a VPS and this is my first big linux venture. I am the only person who has access to it. My question ...
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votes
6answers
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How to setup linux permissions for the WWW folder?

Updated Summary The /var/www directory is owned by root:root which means that no one can use it and it's entirely useless. Since we all want a web server that actually works (and no-one should be ...
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votes
5answers
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How do I grant start/stop/restart permissions on a service to an arbitrary user or group on a non-domain-member server?

We have a suite of Windows Services running on our servers which perform a bunch of automated tasks independently of one another, with the exception of one service which looks after the other ...
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votes
6answers
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GRANT SELECT to all tables in postgresql

Is there a one-liner that grants the SELECT permissions to a new user postgresql? Something that would implement the following pseudo-code: GRANT SELECT ON TABLE * TO my_new_user;
35
votes
2answers
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Postgresql: what does GRANT ALL PRIVILEGES ON DATABASE do?

I'm trying to grant all privileges on all tables of a given database to a new postgres user (not the owner). It seems that GRANT ALL PRIVILEGES ON DATABASE my_db TO new_user; does not do that. After ...
33
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2answers
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Why was I able to delete a file owned by root in my home directory without being root?

So I was doing some maintenance on my server earlier today and noticed I was able to delete a file owned by root in my home directory. I was able to reproduce a sample: [cbennett@nova ~/temp]$ ls ...
32
votes
5answers
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what permission to write PID file in /var/run

Ubuntu touch: cannot touch `/var/run/test.pid': Permission denied I am starting start-stop-daemon and like to write the PID file in /var/run start-stop-daemon is run as my-program-user /var/run ...
29
votes
15answers
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Why does sudo command take long to execute?

I've been picking up Linux (Fedora 10, then 11) over the past few months (and enjoying it immensely-- it's like discovering computers all over again, so many things to learn). I've added my user to ...
28
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2answers
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How can I show user's privileges in MySQL?

I know that I can set user's privileges in the following simple way: grant all on [database name].[table name] to [user name]@[host name]; But how can I see existing privileges? I need to see data ...
27
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2answers
871 views

Why is it bad to have root writing files to a directory not owned by root?

This came up in a comment to another question and I'd love it if someone could explain the reasons for this to me. I suggested having Apache log the errors for a given VHost to a user's home ...
26
votes
4answers
7k views

What is the first digit for in 4-digit octal Unix file permission notation?

3-digit: 644 ugo (user group other) 4-digit: 0644 ?ugo (??? user group other) What is the first octal digit for in 4-digit octal Unix file permission notation?
26
votes
1answer
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Vagrant set default share permissions

When running a vagrant instance the project folder is mounted on /vagrant automatically. However is mounted with the following permissions # ll -d /vagrant drwx------ 1 vagrant vagrant 612 Jun 13 ...
25
votes
1answer
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Why doesn't SSHFS let me look into a mounted directory?

I use SSHFS to mount a directory on a remote server. There is a user xxx on client and server. UID and GID are identical on both boxes. I use sshfs -o kernel_cache -o auto_cache -o reconnect -o ...
23
votes
1answer
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What Should be the Permissions of Apache SSL Directory, Certificate, and Key?

I have my cert.pem and cert.key files in /etc/apache2/ssl folders. What would be the most secure permissions and ownership of: /etc/apache2/ssl directory /etc/apache2/ssl/cert.pem file ...
22
votes
3answers
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Linux: how to give a user permission to restart apache?

I have a script running under a non-root user which, under certain conditions, should restart apache httpd. What would be the simplest way for me to allow the user to do that? I'm using Ubuntu ...
22
votes
5answers
9k views

Minimum permissions for a user to perform a mysqldump?

I want to start scheduling remote mysqldump crons, and I'd prefer to use a special account for that purposes. I want to grant that user the minimum permissions for getting a full dump, but I'm not ...
22
votes
7answers
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How to workaround the NTFS Move/Copy design flaw?

As anyone that has dealt with file server permissions is aware, NTFS has an interesting design feature/flaw known as the Move/Copy problem. As explained in this MS KB article, the permissions for a ...
22
votes
4answers
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Which permissions/rights does a user need to have WMI access on remote machines?

I'm writing a monitoring service that uses WMI to get information from remote machines. Having local admin rights on all these machines is not possible for political reasons. Is this possible? What ...
21
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2answers
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chmod -R makes files in child folders ureadable for some reason

I was adjusting the permissions when setting up some WordPress themes, and ran chmod 664 -R theme-dir/* It worked fine on the files in the root of the directory, but all the files in subdirectories ...
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5answers
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Files mounted over NFSv4 are owned by 4294967294, UIDs and GIDs match

I have two identical linux machines (identical images launched in amazon EC2) and I am trying to mount an exported directory over NFSv4. Here is what the mounted directory looks like on the client ...
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4answers
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Is a reboot required to refresh permissions after adding a user to a new group?

On ubuntu server, I've noticed more than once now that after adding a user to a group that user doesn't have group permissions until I reboot the system. For example: User 'hudson' needs permission ...
19
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1answer
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What does the @ symbol mean in a file's permission settings?

I'm on MacOSX, I did ln -s on a directory and these are the results: -rwxrwxr-x@ 1 shiki admin 970332 Mar 6 16:38 apc.so -rwxrwxr-x@ 1 shiki admin 653884 Mar 6 16:38 eaccelerator.so ...
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7answers
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Copy permissions to identical tree on linux / unix

i have a tree of files with correct permission. then i have a (filewise) identical tree (with different file contents tough) with wrong permissions. how can i transfer the permissions layout from ...
18
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2answers
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What is the sticky bit in UNIX file systems? When is it used?

What is the sticky bit in a UNIX file system? As an admin when and how would you use it?
18
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1answer
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User accidentally messed up a Robocopy command and caused a bunch of folders to get created with corrupt security

We had a user run a robocopy command to copy some files but unfortunately the user accidentally messed up the syntax. Something like: robocopy "\\server1\share\Accounting" ...
18
votes
2answers
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“'' is not a valid login or you do not have permission” on sql server installation

I have tried installing SQL Server 2008 multiple times on my machine, and I always receive this error about 3/4 of the way through: '' is not a valid login or you do not have permission. I use SYSTEM ...
18
votes
1answer
31k views

What can user do with VIEW SERVER STATE permissions?

In SQL Server 2008 there is a permissions VIEW SERVER STATE. What rights this permission give to user? What SQL Server mean by SERVER STATE?
18
votes
2answers
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Amazon Cloudfront with S3. Access Denied

We're trying to distribute out S3 buckets via Cloudfront but for some reason the only response is an AccessDenied XML document like the following: <Error> ...
17
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6answers
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How to change owner of mount point

We have moved mysql data directory to another disk, so now /var/lib/mysql is just a mount point to another partition. We set the owner of the /var/lib/mysql directory to mysql.mysql. But everytime we ...
17
votes
2answers
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Although 80 and 443 are system ports, how are most web servers able to bind to them anyway?

Running a web-service that binds to port 80 usually doesn't require sudoer privileges. Since ports 80/443 are system ports, meaning they can only be used by privileged users, how come those services ...
17
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4answers
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How can I set full premissions to a user in a specified dir?

How can I set full permissions to a user in a specified dir in linux?
17
votes
2answers
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MySQL: creating a user that can connect from multiple hosts

I'm using MySQL and I need to create an account that can connect from either the localhost or from another server, i.e. 10.1.1.1. So I am doing: CREATE USER 'bob'@'localhost' IDENTIFIED BY ...
16
votes
5answers
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Bash Scripting: Require script to be run as root (or with sudo)

I'm trying to write a bash script (in Ubuntu) that will backup a directory using tar. How can I do a check in the script so that it can only be run as root (or with sudo)? For instance, if a user ...
16
votes
2answers
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Using ICACLS to set permissions on user directories

I'm trying to reset permissions on user directories and having a bit of trouble with the last step of my script. My script basically takes ownership of the entire user directory, resets the ...
15
votes
1answer
11k views

Upstart: allowing a normal user to stop and start my custom service

I have got my webserver application starting on boot using upstart. This is the upstart script: # web app node upstart file at /etc/init/webapp.conf description "web application" start on started ...
15
votes
5answers
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Apache: Isn't chmod 755 enough to set up symlink or alias on Apache httpd on Mac OS 10.5?

On my Mac OS 10.5 machine, I would like to set up a subfolder of ~/Documents like ~/Documents/foo/html to be http://localhost/foo. The first thing I thought of doing is using Alias as follows: Alias ...
15
votes
1answer
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nginx: no permission to bind port 8090 but it binds to 80 and 8080

I'm struggling with some strange permission related behavior: when I configure nginx to listen to port 8080 everything works as expected, but when I use any other port I get something like 2014/01/10 ...
14
votes
2answers
2k views

Linux ssh: allow public-key authentication without giving user read rights to private key

Users logged in on my Linux server should be able to ssh to a specific remote machine with a default account. The authentication on the remote machine uses public key, so on the server the ...
14
votes
1answer
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How does one get setfacl to set ACL permissions recursively on Linux?

I'm setting up a new server and wanted to give ACL a shot over the chown:chgrp:chmod style permissions. The man page for setfacl indicates that the '-R' option can be used to set the ACL ...
14
votes
4answers
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Can't connect to default admin share on Windows 2008

I have a Windows 2008 Server that I'm trying to connect to the default administrative share \\servername\c$ I can connect to it using the default Administrator account. But if I try to connect using ...
14
votes
4answers
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Restrict access to IIS site to an AD Group

Is it possible in IIS to set up a site in IIS and only let users of a certain AD Group get access to it?
13
votes
3answers
907 views

Which MySQL users are necessary?

My MySQL server has a number of strange users which I did not add. Are these all necessary? 'root'@'127.0.0.1' 'root'@'localhost' 'root'@'SERVERNAME' 'root'@'::1' ''@'SERVERNAME' ''@'LOCALHOST' If ...
13
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Is it normal to give 'users' administrator access to their company PC?

I have a user who wants to be a administrator of his work PC, he's made some story up about how he can't work without it so I'm told to "fix it" (as if it is a fault he's logged on as a user!). My IT ...
13
votes
4answers
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Gaining administrator privileges in PowerShell

I only have one account on my Windows Vista machine, and that user has administrative privileges. However, when I try to execute a command within PowerShell to kill a certain process, I'm greeted with ...
13
votes
4answers
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linux/setfacl - Set all current/future files/directories in parent directory to 775 with specified owner/group

I have a directory called "members" and under it there are folders/files. How can I recursively set all the current folders/files and any future ones created there to by default have 775 permissions ...
13
votes
3answers
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Windows File Permissions and Attributes

I'm somewhat confused about the whole Windows file security scheme. I come from a unix background, so I don't fully understand the relationship between file permissions/security settings and the ...
13
votes
3answers
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What User Should NGinx and PHP be running as?

Permissions are something that have confused for me a while with Linux. So at the minute both my NGinx and PHP-FPM instances are running with the user and group : www-data Is this standard? I ...