CHMOD (Change Mode) is the file permission system used by UNIX based servers which Site5 uses. The permissions appear as a set of 3 numbers in a row. In order of appearance, the numbers represent user, group, and other’s access level.
Without going into too much detail, here are some basic examples of the most commonly used permissions.
755 = Can be viewed and executed by anyone, can only be modified by the user.
-This is most commonly used on folders and can be used as a substitute for 777 on our servers.
644 = Can be viewed by anyone, but can only be changed by the user.
-This would be used for php and other file types.
444 = Can be viewed by anyone, can’t be modified without changing the CHMOD.
-This would be used for protecting configuration files.
-Note: This permission can’t be set via FTP
Another permission level that is mistakenly used often is 777. Using this permission level is very dangerous because it means that anyone can read, execute and change the file. In fact we have prevented files that have group or other write access from running for your security. Attempting to use permission 777, 757 or 775 will cause an error 500 page to appear when trying to access that file in a browser. You can confirm this by checking the SiteAdmin/cPanel error log. You will see entries similar to the following.
[Wed Aug 22 12:49:42 2012] [error] [client 22.214.171.124] SoftException in Application.cpp:264: File “/home/user/public_html/test.php” is writeable by others
[Wed Aug 22 12:49:23 2012] [error] [client 126.96.36.199] SoftException in Application.cpp:256: File “/home/user/public_html/test.php” is writeable by group
Note: If a script or application requests you to use 777 permissions, you can substitute it with 755 on our servers and it should work correctly.
For instructions on how to change permissions, please see one of the following articles.