CHMOD - Undertanding File Permissions on a Unix-Based Server

The basic command for changing file permissions in unix based operating systems is the 'chmod' command. This command is executed with a set of parameters after it. With most FTP clients, you can simply select the filename you want to change the permissions of, right click, and choose the chmod command.

There are three main groups of permissions when dealing with the chmod command. The three groups are yourself or owner, your unix group, and everyone else. A typical chmod command would look like this - 'chmod 755' This allows you to add, remove or rename files as well as read or edit a file. It also specifies that your unix group and everyone else can only read and edit the file in question. They can't add, delete, or rename the file.

How the numbers in the chmod command work

There are three types of permissions that can be given to a file. They are read, write, and execute. The read permission is assigned a value of 4, the write permission is assigned a value of 2 and the execute permission is assigned a value of 1. So when a chmod command specified the digit 7 as the first number, it means that all three types of permissions are to be assigned to it. If a party is assigned a value of '0' then it means it has no rights whatsoever to a file. '6' tells the server that the user can read and write to the file but can't execute it. I think you get the idea.

Common permissions to set

Most of your html files will do fine with a permission of 644. Most script files will need a permission of 755. Any configuration files in a script package will often need a file permission of 777. Be very careful about assigning a file permission of '777' for everyone. With this permission, it means that anyone who gains access to your server will be able to add, remove, rename, read or edit the file. It is always a good idea with security in mind to assign the least amount of permissions necessary to get the job done.

An FTP client can keep things simple

Most people on shared servers will not have access to a command line to be able to use the chmod command. For most people, changing file permissions will be done through an FTP client. To do this, right click on the file you want to alter, and choose the chmod command. You will usually get a popup that will show nine checkboxes. The will be arranged in three rows. On the left you will usually see Read, Write, and Execute for the row headings. You can accomplish the same thing as typing in the numbers above by clicking on one, two or three boxes for each party. Once you're done, you click the apply or ok button and the file permissions will be changed.

If you keep in mind that you need to always go with the most restrictive file permissions possible that still allows your files to execute, and that there are three parties to define permissions for, you'll do fine. The three parties again are the owner, group, and everyone else.

This article was written by Joe Duchesne, president of http://www.yowling.com/, a web hosting company that specializes in helping online business owners increase their website traffic. Copyright 2004 Yowling. Reprint Freely as long as you link back to my website from this resource box.

In The News:


pen paper and inkwell


cat break through


Web Hosting: Which Is The Host With The Most?

So you want to publish a web site do you?... Read More

Avoid Getting Ripped Off By A Hosting Company

Chances are if you host multiple domains or websites you... Read More

Web Hosting - Choose Affordable, Cheap Web Hosting

The Basics:Web hosting offers you the opportunity to put your... Read More

Cheap Web Hosting Package? eCommerce Web Hosting? - Choosing A Web Hosting Provider

One of the important decisions you'll make when you decide... Read More

Hosting Options for an Ecommerce Web Site

Deciding how to host your ecommerce Web site and what... Read More

Bound To Your Old Expensive Web Host by Fear?

You're not alone! Many people are bound to the old... Read More

Web Hosts: Helping Us Navigate Through This Future Techno-World

Computers, Internet, Web sites?what do they all mean? Hey, you're... Read More

Reseller Hosting: The Good and The Bad!

Reseller webhosting can be a great way to earn some... Read More

How to Choose a Web Host - Frequently Asked Questions

In this article you'll be provided with helpful information about... Read More

Criteria of Choosing an Ideal Web Hosting Company

Before we talk about what it takes to... Read More

How To Find The Best Web Hosting For You

Deciding on the best web hosting company for a web... Read More

Top 5 Mistakes that May Drive Your Visitors Away in Less Than 2 Minutes

You took the leap. You set up a website to... Read More

Choosing The Wrong Server Will Literally Make Or Break You

Choosing the right web server will be one of the... Read More

Web Hosts - Not All Are Created Equal

Many people think that all web hosts offer the same... Read More

Buyer Beware: Web Hosting, Registration, and Site Building All in One Package Nightmares

Starting out in any type of online marketing or Internet... Read More

Dedicated Server Price Check

The price of dedicated hosting services has really come down... Read More

Web Hosting: 4 Factors in Choosing a Hosting Company

When choosing a web hosting company there are a whole... Read More

In Search of Webhosting: First Understand the Industry

In search of a webhosting company for personal or small... Read More

Virtual Private Servers (VPS) Web Hosting

A Virtual Private Server (VPS), also referred to as Virtual... Read More

The Perfect Support

Hosting Support ? An IntroductionImagine yourself as a person running... Read More

Hosting Your Own Web Server: Things to Consider

Are you disgusted or disappointed with your current web host?... Read More

Cheap Web Hosting, What To Look For And What To Stay Away From

"Bargains for sale, Unlimited Hosting for only a Dollar.""Get your... Read More

Dedicated Web Hosting Is Easy When You Know These 3 Timesaving Secrets

Dedicated web hosting has its difficulties and problems from time... Read More

How to Choose the Web Site Hosting Service thats Right for You

There are few things as critical to your e-business success... Read More

What You Should Know About Your Web Host

Yesterday I received a nice email in my inbox, I... Read More

Hosting Your Way All The Way To The Bank

Let's face it, the Internet is here for good. Today's... Read More

Finding a reliable hosting provider

The website hosting business is very competitive these days with... Read More

Is Free Hosting Really Free?

Sooner or later, as everyone finds out, nothing in this... Read More

Server Uptimes Revealed: The Hidden Cost of Cheap Hosting

We often see server uptime statistics when looking for hosting... Read More

How Much Bandwidth Does Your Web Site Need?

One of the most common concerns people have when deciding... Read More

Unlimited Wealth Creation Through Reseller Hosting

Web hosting can be an exciting business start up for... Read More

The Top 15 Essential Ingredients of Every WINDOWS HOSTING Plan (Package)

First things First. Why would you like to have Windows... Read More

Top 6 Ways to Promote Your Web Hosting Business Part 2

Here are the following three methods that can help you... Read More