Downtown Doug Brown

There are tons of instructions out there for setting up WordPress on a lighttpd server with WP Super Cache. A quick Google search will show you what I’m talking about. I’m not totally happy with them though — it usually boils down to enabling mod_magnet and using a lua script. It’s not too surprising that it requires a bit of trickery because the main instructions that come with WP Super Cache are designed with Apache in mind.

I’d like to share the setup I use on this blog, which takes more manual effort initially but no longer requires the use of a lua script.

I first obtained these instructions from a blog which no longer exists, but the original instructions are still available from the wonderful Internet Archive. Since the original page is no longer around in Google results, I feel like I need to keep the instructions alive. So…here they are, in my own words and modified for a newer version of lighttpd:

First of all, set up WP Super Cache for mod_rewrite mode. It’ll warn you that mod_rewrite isn’t installed and the rewrite rules must be updated — this is perfectly OK because we’re not using Apache.

Now, in the main WordPress directory, create symlinks to everything in the wp-content/cache/supercache/www.domain-name.com directory. Here’s an example symlink command for the “2010” directory:

ln -s wp-content/cache/supercache/www.domain-name.com/2010 2010

I had to create the following symlinks on my server:

2010, 2011, 2012, category, contact, index.html, and microcontroller-lessons

Every time you add a new page with a root directory URL or another year goes by, you will need to add an appropriate symlink or else the supercaching for that page won’t be active–it’ll be served through PHP instead, so the site won’t break if that happens — it’ll just be inefficient.

OK. Now that you have that done, disable directory listings, set the 404 error handler to /index.php, and ensure that index.html comes before index.php in the list of index file names. That last one about index.html being in front of index.php simply ensures your main blog page is served supercached correctly. Anyway, this can all be done in lighttpd.conf:

server.error-handler-404 = "/index.php"
dir-listing.activate = "disable"
index-file.names = ( "index.html", "index.php" )

That’s it! It’s about as simple as it can get.

Is it perfect? No, not at all. It doesn’t matter if you’re logged in or not — if a supercached version of a page exists and you go to its URL, you will get the supercached version rather than a newly-generated version of the page–meaning you don’t get the cool WordPress toolbar at the top. So it isn’t smart enough to look at your cookies or anything like that to only serve supercached files to non-logged-in users. In my case, I don’t really care — I can still access the WordPress Dashboard and that’s all that really matters to me.

It’s also kind of annoying that you have to create a new symlink for everything that is in the “wp-content/cache/supercache/www.domain.com” directory, but I can live with it.

It appears to work because if a supercached version of a page doesn’t exist already, a 404 error occurs, which passes the request onto /index.php, which figures out the original request.

Thanks again to the (now defunct) Zash Blag for the original instructions. There may be better solutions available than this — if there are, please leave a comment! I would definitely be interested in trying them out.