Apache

Varnish is a web application accelerator that helps to speed up websites. It works by sitting in front of the web server and caching web pages that are served by it.

When a request for a web page is made Varnish passes this request on to the web server, which then responds to the request as it normally would. Varnish then caches the result of this request before sending it to the user.

Varnish is a web application accelerator that provides an easy speed increase to most web applications and Drupal is no exception. It works by creating a reverse proxy service that sits in front of your web server and caches traffic that comes through it. When the page is requested, Varnish forwards the request to the web server to complete the request, the response that comes back from the web server is then cached by Varnish. This means that the next request to the same page is served by Varnish and not the web server, which results in a large speed increase.

The upshot of using Varnish with an application like Drupal is that when a request is made there is no hit to the web server (and thus PHP) and no hit to the database. Varnish works best with Drupal with anonymous traffic, as authenticated traffic requires cookies and custom HTML. Even so, you can see massive speed increases for any anonymous traffic on the site.

Many systems and applications require certain access to certain ports and protocols. When installing these systems using Ansible it is necessary to also open up the needed ports so that the systems can function correctly. As there is no iptables module in Ansible the shell command is needed to add the iptables rules.

As an example, here is a task that adds a iptables rule to allow Apache to communicate on port 80.

- name: Apache | add apache iptable rule
  command: /sbin/iptables -I INPUT 1 -p tcp --dport http -j ACCEPT -m comment --comment "Apache"
  sudo: true

Once this is in place you might need to save and/or restart iptables in order to get the rule to be permanently saved. The following two rules will save the iptables rule and restart the iptables service. Note that these commands are specific to Ubuntu and so might not work on your system setup.

When setting up staging sites or similar I often add a simple Apache authentication check in order to stop everyone from viewing the site. This is also useful in stopping search engine spiders from accessing a site with testing content on it, which generally causes trouble. It isn't amazingly secure, but it keeps almost everyone out.

Phing is an awesome tool for automating things and I use it more and more for automating all kinds of different tasks. One of the tasks that I don't tend to do all that much is setting up a new local virtual host for Apache on my development machines. I know how to do it, but there is always something I forget to do, or a convention that I don't follow which means that I have to repeat myself at a later date to fix something I have missed.

So to make my life a little easier I decided to create a Phing build file to automatically create a virtual host and the everything associated with it in one go. Essentially, I would need to do the following tasks:

I recently built a Drupal site on an Apache server setup and everything seemed fine until someone running IE8 tried to download a .docx file. For some reason IE8 insisted that this file was a .zip file and would open it as such, causing a bit of confusion as to what the problem was. I assumed that this was due to the mime type of the file not being set properly, but I decided to do a quick search to see if I could find anything to corroborate this. I thought it might be something odd that IE8 was doing as everything else was downloading the file perfectly.

After wading through multiple support forums and finding very little of any help I eventually gave up and went with my first hunch and set the mime type for the .docx file extension in the sites .htaccess file. Here is the rule I used:

Use the following rules in your Apache configuration (or your .htaccess file) to redirect all traffic from one domain to another. This also keeps the query string in place so that the user isn't just dumped to the homepage.

RewriteEngine on
RewriteCond %{HTTP_HOST} !^www\.example\.com$ [NC]
RewriteRule ^(.*)$ http://www.example.com%{REQUEST_URI} [L,R=301]

These rules are mod_rewrite dependent, so you'll need that module enabled in your Apache install.

I was recently setting up a localhost environment with Ubuntu 11 and after adding all of my needed VirtualVost directives I found that I could start/restart the server but that I found the following error when trying to start the server.

user2@machine:/etc/apache2/sites-available$ sudo apache2ctl -k start
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName

To fix the problem you needed to add a simple directive to the Apache httpd.conf file. In order to access this file you'll need be have admin access, so open up a terminal window and type the following command.

Following on from the post about starting and stopping MySQL using .bat files I decided to add commands to these files that also controlled Apache in the same way. This turned out to be a lot easier than trying to start and stop MySQL as the command line commands for httpd executable worked very well in .bat files.

So, to start Apache use the following line.

"C:\Program Files (x86)\Apache Software Foundation\Apache2.2\bin\httpd" -k start

And to stop the server use the following line.

"C:\Program Files (x86)\Apache Software Foundation\Apache2.2\bin\httpd" -k stop

Getting started with SVN on Ubuntu takes only a few minutes, and enabling web access to the repository is also very straightforward.

First (in order to actually serve the files) you need to install Apache, open up a terminal window and run the following command. This will ensure that Apache is installed if you unselected it for some reason during the install.

sudo apt-get install apache2

Note the use of the sudo command. This will run the command you give it as a super user as normal users will not generally have access to install software like this. When you use sudo you will be prompted for the super user password. Next, use the following command to install SVN.