WordPress under Nginx and Varnish with W3TC

When it comes to my per­sonal Internet pres­ence, I am an invet­er­ate tin­kerer. I like to exper­i­ment and I like to run things my way. (This is in con­trast to my pro­fes­sional rec­om­men­da­tions as a con­sul­tant, where I like con­ser­v­a­tive and tested.)

As such, despite hav­ing no prob­lems with my pre­vi­ous host (Laughing Squid, which I still rec­om­mend), I decided to switch to a Virtual Private Server (VPS) so that I could have more flex­i­bil­ity and con­trol over my server envi­ron­ment. I selected VM Storm based on a review of  “low-end” VPS providers (since this is my per­sonal tin­ker­ing plat­form I don’t need to pay extra for a high-end name). I then added Nginx as my Web server, Varnish as a front-end cache, WordPress for blog­ging, and W3TC as a WordPress per­for­mance enhancer.

The Virtual Private Server

Remember that with a basic VPS, no one admin­is­ters the sys­tem for you (unless you pay extra, of course). You need to make your own size esti­mates, then install and con­fig­ure your Web server and every­thing else (the OS itself was installed by the provider). This, of course, is exactly what I was look­ing for, since I wanted to experiment.

While I prob­a­bly could have made it work with an even more com­pact envi­ron­ment, I went with 512 MB of mem­ory to give me some breath­ing room. I decided on Ubuntu 11.10 Server because I’m famil­iar and com­fort­able with Ubuntu, and because there are lots of online Ubuntu resources and help available.

The Web Server

I’m most famil­iar with Apache, a free, open-source, incred­i­bly flex­i­ble and pow­er­ful Web server. But since I was inter­ested in exper­i­ment­ing, I decided to try an alter­na­tive: Nginx(“engine x”), a fast and com­pact HTTP server that now pow­ers sites like WordPress.comand CloudFlare. It’s known for its resource effi­ciency and speed, so it’s a per­fect choice for smaller VPS setups (and it too is open source and free).

(Note: I thought about Lighttpd, another fast and com­pact Web server, but Nginx proved be eas­ier for me to get going the way I liked.)

The Front-End Cache

Nginx is fast, but I wanted more. So I put Varnish in front of Nginx. What’s Varnish?

Varnish Cache is an open source, state of the art web appli­ca­tion accel­er­a­tor. You install it on your web server and it makes your web­site fly.

Basically, it’s a server-side caching proxy. It lis­tens for HTTP requests, serves them really fast if they’re in its cache already, or for­wards the request to Nginx if they’re not. Want to sur­vive a Slashdotting? Use Varnish. (And then add CloudFlare for good measure!)

The Database

I went with MySQL (of course). It works. I added php­MyAd­min to help admin­is­ter it, and put that behind Nginx run­ning SSL with a self-signed cer­tifi­cate. I could have bought an SSL cert, but what’s the point? I know who I am, and no one else needs SSL access to my install any­way. (I’m not sell­ing stuff through my site.)

The Software

While I could have exper­i­mented with other solu­tions for blog­ging, I wanted to stick withWordPress. It’s flex­i­ble, exten­si­ble, and nice to work with. It isn’t always the fastest or most opti­mized thing out there, but that’s what Nginx and Varnish are for!

WordPress was really designed for a LAMP envi­ron­ment: Linux, Apache, MySQL, and PHP. So replac­ing Apache with Nginx had the poten­tial to cre­ate some chal­lenges – which it did! But for­tu­nately, Nginx is an increas­ingly pop­u­lar choice, and one of the most pow­er­ful WordPress plu­g­ins out there (W3TC–W3 Total Cache) has added sup­port for it, which made every­thing easier.

W3 Total Cache

W3TC is more than a cache. It bills itself as a “per­for­mance frame­work,” and although I often pre­fer the Unix “small-tool” phi­los­o­phy, W3TC really shines. To be hon­est, it’s options for per­for­mance enhance­ments encour­aged me to think about using a VPS in the first place, just so I could play with them. It han­dles disk and data­base or object caching (using mem­cache or PHP APC), content-delivery net­works (like Amazon CloudFront), and even Varnish cache purging.

Resources and How-To Guides

• WordPress on Nginx (nginx.org)
• Supercharge WordPress (openlogic.com)
• How to build the ulti­mate Ubuntu/Lighttpd/PHP/MySQL server, and keep it run­ning(nanotux.com)
• Sample Varnish con­fig for WordPress (github.com)