Summary: how to diagnose and eliminate the xmlrpc.php WordPress exploit when it’s clobbering your web server. You’ve been running a public Ubuntu 12+ and Apache/LAMP web server for a while now. Until recently everything has worked fine, but suddenly your server is struggling to display even static pages. Sometimes content takes forever to load, and […]
Ubuntu 16.04 LTS has been out for a little while now, and its standard repos offer some nice enhancements over Ubuntu 14: Apache 2.4.18, PHP 7, and MySQL 5.7.12 The process for creating a basic LAMP web server is also streamlined, as a couple of bugs that plagued Ubuntu 14.04 are now eliminated. To create […]
This is a shorthand summary of web server performance and caching systems as of March 2016. General disclaimer: I try to link benchmark results that seem relatively neutral, but as with any survey or study or benchmark roundup, the most pertinent question is cui bono? Ultimately the only reliable benchmarks are those you run yourself […]
Recently I was testing some web servers with the SSL Labs SSL web server test. This article describes the fixes I applied to Ubuntu Server 12.04 to get an A+ on the test. The SSL Labs Test Auditing the SSL certificates on your web server occasionally is a good idea, since you always want to […]
Using Varnish and Pound together is a relatively easy way to ensure the Varnish cache works for both SSL and non-SSL web sites. Varnish is a general-purpose web cache that can make your web sites and applications run substantially faster for your visitors while reducing the overall load on your web server. It works by […]
By default most Apache web servers — at least prior to Apache 2.4 — run Apache’s Prefork MPM (multi-processing module). Prefork works OK and offers the greatest compatibility with existing Apache modules, but it consumes a relatively large amount of memory because it spawns many processes that each handle one connection at a time. Prefork […]
Ubuntu 14.04 LTS has been out for a while now, and it offers some nice enhancements over 12.04 in its default repos: Apache 2.4, PHP 5.5, and MySQL 5.5.3x. Starting from a bare server image, here’s how to get an Ubuntu 14 web server up and running for PHP. Install the Web Server $ apt-get […]
Update April 2018: I’d suggest using Let’s Encrypt for this instead. I do this just infrequently enough to forget the details. So here’s the process for purchasing and installing a SSL certificate for https on your Linux/Apache web server (using Ubuntu 12.04 and Apache 2.2 here): Generate Local Key/CSR, Purchase SSL Certificate Generate your key […]
A quick summary of the major Linux/Unix Apache multi-processing modules. Prefork Default MPM in Apache < 2.4 Consumes more RAM than threaded MPMs like Worker or Event Threadless design is safe for non-thread-safe modules like mod_php Spawns child processes that each deal with one request at a time Performs poorly on high-traffic servers with many concurrent […]