The Definitive Guide to htaccess Techniques: Do’s and Don’ts
- Posted in PHP
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Of all the elements of web design and coding, htaccess can be one of the most intimidating. After all, it’s an incredibly powerful tool and one that has the potential to completely break your site if you’re not careful.
Below are a dozen basic htaccess techniques and tips to get you started. They’re not nearly as intimidating as many people expect, and if you study the code for a few minutes, I’m sure you’ll quickly grasp exactly how they work and why.
After that are a few bewares and don’ts for working with htaccess to help keep you out of trouble, and some more resources for further working with htaccess.
12 Basic htaccess Tips:
1. Create a custom error page.
.htaccess on a Linux Apache server makes it easy to create your own custom error pages. Just create your custom error page files and then add this code to your .htaccess file:
ErrorDocument 401 /401.php ErrorDocument 403 /403.php ErrorDocument 404 /404.php ErrorDocument 500 /500.php
(Obviously you should replace the “/500.php” or whatever with your own file path and name.)
2. Prevent directory browsing.
If you don’t include an index file in a directory, visitors can browse the directory itself. But preventing that is as easy as adding a single line to your .htaccess file:
Options All -Indexes
3. Set the default page of each directory.
If you don’t want to use an index page in each directory, you can set the default page visited when someone reaches (like an about page or a page offering the newest content) that directory by adding this:
DirectoryIndex news.html
(And of course you’d replace the “news.html” bit with whatever you want to use as the default.)
4. Set up a 301 redirect.
If you move around the structure of your site and need to redirect some old URLs to their new locations, the following bit of code will do so for you:
Redirect 301 /original/filename.html http://domain.com/updated/filename.html
5. Compress file output with GZIP.
You can add the following code to your htaccess file to compress all of your JavaScript, CSS and HTML files using GZIP.
<IfModule mod_gzip.c> mod_gzip_on Yes mod_gzip_dechunk Yes mod_gzip_item_include file \.(html?|txt|css|js|php|pl)$ mod_gzip_item_include handler ^cgi-script$ mod_gzip_item_include mime ^text\.* mod_gzip_item_include mime ^application/x-javascript.* mod_gzip_item_exclude mime ^image\.* mod_gzip_item_exclude rspheader ^Content-Encoding:.*gzip.* </IfModule>
6. Redirect to a secure https connection
If you want to redirect your entire site to a secure https connection, use the following:
RewriteEngine On
RewriteCond %{HTTPS} !on
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}
7. Block script execution.
You can stop scripts in certain languages from running with this:
Options -ExecCGI AddHandler cgi-script .pl .py .php .jsp. htm .shtml .sh .asp .cgi
Just replace the types of scripts you want to block.
8. Force a file to download with a “Save As” prompt.
If you want to force someone to download a file instead of opening it in their browser, use this code:
AddType application/octet-stream .doc .mov .avi .pdf .xls .mp4
9. Restrict file upload limits for PHP.
You can restrict the maximum file size for uploading in PHP, as well as the maximum execution time. Just add this:
php_value upload_max_filesize 10M php_value post_max_size 10M php_value max_execution_time 200 php_value max_input_time 200
Line one specifies the maximum file size for uploading; line two is the maximum size for post data; line three is the maximum time in seconds a script can run before it’s terminated; and line four is the maximum amount of time in seconds a script is allowed to parse input data.
10. Enable File Caching.
Enabling file caching can greatly improve your site’s performance and speed. Use the following code to set up caching (changing the file types and time values to suit your site’s needs):
#cache html and htm files for one day <FilesMatch ".(html|htm)$"> Header set Cache-Control "max-age=43200" </FilesMatch> #cache css, javascript and text files for one week <FilesMatch ".(js|css|txt)$"> Header set Cache-Control "max-age=604800" </FilesMatch> #cache flash and images for one month <FilesMatch ".(flv|swf|ico|gif|jpg|jpeg|png)$"> Header set Cache-Control "max-age=2592000" </FilesMatch> #disable cache for script files <FilesMatch "\.(pl|php|cgi|spl|scgi|fcgi)$"> Header unset Cache-Control </FilesMatch>
(Time shown for max-age is in seconds.)
11. Protect your site from hotlinking.
The last thing you want is for those stealing your content to also be able to embed the images hosted on your server in their posts. It takes up your bandwidth and can quickly get expensive. Here’s a way to block hotlinking within htaccess:
RewriteEngine On
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://([ -a-z0-9] \.)?domain\.com [NC]
RewriteRule \.(gif|jpe?g|png)$ - [F,NC,L]
(Of course you’ll want to replace the domain\.com with your own domain name.)
12. Disguise your file types.
You can disguise all of your file types by making them appear as PHP files. Just insert this snippet in:
ForceType application/x-httpd-php
8 Common htaccess Mistakes and Don’ts:
- Be careful of spelling- .htaccess is not forgiving of spelling errors.
- htaccess is case sensitive. If something is shown in the examples with a capital letter, make sure it’s capitalized in your htaccess file.
- Consider your caching needs carefully before setting it up. If your site is almost entirely static, you can set longer cache times. If your site changes daily, make sure you adapt which files will cache for how long. There’s nothing worse as a visitor than coming back to a site thinking there’s been an update and not seeing it.
- Don’t forget to comment out your notes within the file. This is done by adding a # before the comment line.
- Always test your site immediately after making any changes to your htaccess file. One mistyped character could make the difference between your site working and being down for hours before you realize what’s happened.
- On that note, always make sure you backup your htaccess file before making any changes. That way, if there is a problem, you can easily swap back in the old file.
- Make sure any essential htaccess functions you’ve included are cross-browser compatible. There are certain things some browsers just won’t support (one example is with certain methods for forcing file downloads).
- Remember when protecting a web directory with htaccess, that unless it’s restricted to https access, the password could be sniffed (as your authentication will be done over an un-secure connection).
- 21 Very Useful htaccess Tips and Tricks
- 5 htaccess Tricks Every Webmaster Should Know
- 16 Useful .htaccess Tricks and Hacks For Web Developers
- Stupid htaccess Tricks
- Using htaccess Files for Pretty URLS
More Resources:
Author: Cameron Chapman
Cameron Chapman is a writer, blogger, copyeditor, and social media addict. She’s been designing for more than six years and writing her whole life. If you’d like to connect with her, you can follow her on Twitter or at her Personal Website.
useful techniques, thank you so much..
Great post. Rewrite rules are a little more advanced, but would be cool to see a post about them.
Great, maybe the best guide I’ve ever seen.
Thanks! :)
Excellent post. Great to have all these useful htaccess techniques in one place with clear instructions.
Great tips!
Something to keep in mind is that each of of these tips can be used in the regular Apache configuration file. The syntax is the same.
One thing to keep in mind when thinking about the do’s and dont’s is that whenever possible add these changes to the Apache config file instead of a .htaccess file.
Additional overhead is introduced by enabling the .htaccess file.
Well organized, well written, easy to understand – arguably the best quick guide for .htaccess I’ve seen.
Where were you 6 months ago??
Seriously, really useful stuff,
much appreciated!
Much needed thanks, although enabling GZIP via Htaccess would deserve a little more details. 1&1 users won’t go far with the above example.
Question to Cameron.
In tip 11, you wrote ‘(Of course you’ll want to replace the domain\.com with your own domain name.)’
Do I need to replace like this? ‘http://www.mywebsite\.com’
Do I need http://www. ?
Thanks for the article. I learned something new today. :-)
You would just change the domain.\com to yoursite\.com (leaving in the “\.”) without the “http://www.” (because that’s already included in that line of code). So it would look like this:
http://( -a-z0-9] \.)?noupe\.com [NC]
You can also do it like this:
http://(www\.)?noupe\.com [NC]
Yeah, same thing I’m trying to figure out. Changed “domain” to mine, added it and then got 500 error so that way definitely doesn’t work.
I have another way to prevent hotlinking which enables Google and Bing to hotlink, because most of the tips you can find on the web usually don’t work. Normally, Google has no problem with anti-hotlinking, but Bing has. Yahoo more often than not can hotlink, but sometimes not.
RewriteEngine On
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?mydomain\.com/ [NC]
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?google\.(.+)/ [NC]
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?(.*\.)?google\.(.+)/ [NC]
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?bing\.(.+)/ [NC]
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?(.*\.)?bing\.(.+)/ [NC]
RewriteCond %{HTTP_REFERER} !^$
RewriteRule .*\.(jpe?g|gif|png)$ /error/copyright.bmp [L]
Important: The replacement-image must not have the one of the forbidden suffixes. if you normally use .jpg, you can use .jpe or .bmp.
gr8 post!
thanks…
Hey! Nice techniques but i wanna know if you can show me something that i want a lot.. it’s about to show a maintenance page.. the idea is that i create a file (www.myblog.com/maintenance.html) and via .htaccess i make that when someone visit any post (www.mypage.com/somepostinmyblog.html) it will show the maintenance page but the important thing is that in the addres bar, the url doesn’t show my maintenance.html page url, instead, it still showing the url of the post (www.mypage.com/somepostinmyblog.html) but with the content of (www.mypage.com/maintenance.html).. hope you understand me and help me :)!
I’m honestly not sure about this one. I would start by searching for tips on URL masking. It might be possible to do this with mod_rewrite. I know it can be done, but I’m not sure if htaccess is the best way to go about it or if there’s a better solution. It’s not something I’ve ever needed to do before.
These are some really useful techniques and are well written and easy to understand. Thanks for the great article.
This definately Rocks!
Thanks.
Unfortunately I cannot print this page.
Print Preview in Firefox 3.0.13 only shows 2 pages….
in Opera 9.6.2 it is ok
will check if a Firefox-Update will help me ;=)
It is great, thanks.
This is a great resource, thanks so much! its given me some great ideas on things I need to do.
Great Article for newbies !! thank you very much.. !! keep it up
Thank you ;)
Nice tips, I will look to try some! Thanks
Wow, this is an absolutely fantastic collection of commands that designers can reference. Great explanations! Thanks!
Nice list, good to keep it on a second hand ;)
Thanks !!
I don’t believe I’ve ever seen all this in one place before! Bookmarked!
Nice Info Collection Thanks for Sharing it
Quite impressed! All I googled wasn’t as useful as this article :D
This is awesome! Great resource. Thank you for all of this. Definitely bookmarking.
Great reference list. Thanks. Bookmarked!
Great article thanks for sharing – #5. Compress file output with GZIP is a great tip I wasnt aware of this.
You can also block a range of IP addresses from visiting your site. This comes in handy when people in China, for example, only come to your site to steal the design/code/articles.whatever.
For my portfolio site it’s a no brainer. Do people in China, India, Brazil, etc really need to see my US web design portfolio site? Probably not.
This site helps generate an htaccess deny list. I’m sure there are ways around it but it helps.
http://www.countryipblocks.net/
Outstanding overview. Thanks.
Hi there,
Seems like [code]
mod_gzip_on Yes
mod_gzip_dechunk Yes
mod_gzip_item_include file \.(html?|txt|css|js|php|pl)$
mod_gzip_item_include handler ^cgi-script$
mod_gzip_item_include mime ^text\.*
mod_gzip_item_include mime ^application/x-javascript.*
mod_gzip_item_exclude rspheader ^Content-Encoding:.*gzip.*
[/code]
Does not seem to work. I tried adding these lines in .htaccess, but no success. Any idea on what I am missing?
Thanks.
Vishal,
If you’re on a shared hosting service, and your service provider has disabled the mod_gzip apache module, then it won’t work.
Thanks, anything htaccess is something that i always deal with very slowly, usually worried about making a mess of something so i tend to read through things a few times.
Thanks for this info, very useful and practical stuff too.
BTW a small errata;
Options All -Indexes
is a don’t; mixing +/- options and non-+/- options is evil syntax, see https://issues.apache.org/bugzilla/show_bug.cgi?id=33078
Setting MIME-typs to invoke hanlers (ForceType application/x-httpd-php) is bad coding, too. You should use SetHandler.
RewriteCond %{HTTPS} !on
Using the lex. equal (strcmp) is more efficient than a regular expression:
RewriteCond %{HTTPS} !=on
(and others)
if you’d like to match a period and not any character, you should use
And of course, .htaccess files are always a don’t, if one has access to the httpd.conf
Excellent article. I find the gzip trick actually slows my site down as opposed to speeding it up.
It is great, thanks ))
Thanks for this great tips .
I’m having a problem with the caching method , I knew this technique before reading this article and I’m using it in my website , but the visitors can’t see the changes when I try to update something in the css or the javascripts of my website , so how can I flush the cache ??
That’s an excellent guide for anyone. Thanks!
thanks for sharing a great article :)
Thanks for the useful guide. I have fiddled out with htaccess before but all this extra stuff is useful to know.
I intend to bookmark this page therefore I add my own tricks :)
Prevent a txt file (or any file, just change txt to something else) to be loaded
Order allow,deny
Deny from all
password protect one file :
AuthType Basic
AuthName “logged”
AuthUserFile /whateverrep/.htpasswd
require valid-user
dont forget to add a .htpasswd with a proprer login/pasword inside
Regarding (#12) ForceType, you might want to limit it by Directory or Files block so you don’t parse files as PHP that you didn’t mean to (e.g., images).
Regarding (#11) note that some security software and firewalls will block or change the referrer and deny legitimate access to your content. You need to weigh the cost/benefit of this solution to your specific application.
The “High Performance Web Sites” O’Reilly book is a good reference for more info on these topics and more. For the more advanced topics (rewrites, compression, etc.), I would highly recommend fully understanding the impact (client, server, SEO, etc.) and technology before implementing on any public site.
A few things there I forgot about. “logging into the FTP promptly”. Thanks for the article!
Thanks for this. I’ve been looking for something like that for so long. ;)
Thanks a lot dear. These are very useful.