In an earlier post we showed you how to use PHP to compress html files and save valuable bandwidth. Now we will choose a setup where apache will compress the files. This is a more efficient setup for your serverconfiguration.

Installing mod-deflate

When Apache 2 is installed, mod_deflate is automatically installed, but not always enabled. To enable mod_deflate on a debian or ubuntu distribution, we can do:
a2enmod deflate
On another system you have to edit Apache2’s configuration file manually. First locate mod_deflate.so then edit the config file. Add this to the LoadModule section:
LoadModule deflate_module /PATH_TO/mod_deflate.soThen restart Apache
apache2ctl restart

Enable the SetOutputFilter DEFLATE filter

Compression for APACHE 2 is implemented by the DEFLATE filter. To enable compression for documents simply put this filter in the appropriate Directory directives:

SetOutputFilter DEFLATE

But we don’t want to compress picture-files

But we do not want to compress everything! It doesn’t make any sense to compress files like gif, jpg or pdf’s. So we have to make an execption:

// Don't compress picture files
SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ \ no-gzip dont-vary
// Don't compress compressed files
SetEnvIfNoCase Request_URI \.(?:exe|t?gz|zip|bz2|sit|rar)$ \no-gzip dont-vary
// Don't compress pdf's
SetEnvIfNoCase Request_URI \.pdf$ no-gzip dont-vary


Conclusion

Enabling compression is amazingly easy. Simply enable it in your apache directives. To sum it all up:

SetOutputFilter DEFLATE
SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ \ no-gzip dont-vary
SetEnvIfNoCase Request_URI \.(?:exe|t?gz|zip|bz2|sit|rar)$ \no-gzip dont-vary
SetEnvIfNoCase Request_URI \.pdf$ no-gzip dont-var



If you can’t edit your directives, you can alternatively use the .htaccess files in your webroot directory.
That’s all folks!