With a VPS, you get the ability to maintain and modify almost every aspect of the system (except the kernel). This is great if you have some special needs, like a web application that needs MySQL with InnoDB Storage support enabled (most shared hosting offers do not include InnoDB support) or you just want one for your own needs like backups or source control using Subversion where flexibility is more important than being able to support a huge amount of simultaneous requests. A VPS will serve you just fine in one of these cases.

But beware if you get a lot of visitors on your website. I have conducted benchmarks with several VPS hosts, none of them were as fast as the shared hosting provider I’m currently using. Sure I didn’t optimize the Apache, PHP and MySQL config files as much as my professional web host has, but all VPS’ were at least 10 times slower than my shared host. Even the big ones with 1024 MB of RAM. If you install all of the services your average shared hosting company provides (DNS, Mail, Anti-Spam, Anti-Virus), performance will decline even more.

So, given the fact that most people don’t need the flexibility provided by Virtual Private Servers (let’s be honest, a normal LAMP installation will do for most of your hosting needs), they get less speed and they have to do all of the administrative tasks themselves (using Plesk usually doesn’t get the whole job done). If you want to make sure your LAMP installation is secure, you will have to invest even more time.

I hope I could open your eyes for some issues if you’re going to use a Virtual Private Server. If you still think a VPS is right for you, check out different providers and ask them for a trial period or make sure, they provide short-term contracts so you can bail out after a few months if you’re unhappy with their service.

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• An easily customizable grid
• Sensible typography
• A baseline (like the background here)
• Perfected CSS reset
• A stylesheet for printing
• No bloat of any kind

Update: Darren has created a nice guide on how to start working with Blueprint. Check out the guide over here.

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• No installation on client’s architecture needed (no maintenance on the client-side!)
• Your application is always up to date
• You can use a various billing models (monthly, yearly, even per usage)

But shifting away from an employee’s personal desktop or a local network server to some kind of web server (or a load-balanced server-farm) can cause some serious problems. Web apps tend to slow down the more people use them. One way to fight this (not directly, though), is using a sophisticated test tool. The testing itself won’t fix your web app’s performance issues, but it will provide you with a good and reliable way to measure performance while you’re tuning some aspects like the web or database server’s configuration. Getting more out of your servers really depends on how accurately you can measure the changes you’ve made to various configurations.

This is where Apache Jakarta’s jMeter comes into play. Commercial testing applications easily cost thousands of dollars and are often a nightmare to use, thus requiring training courses for their users to attend which make them even more expensive. Apache’s jMeter is an open-source application providing you with most features you will ever need to test your servers or applications. It’s usability also leaves some space for improvement, but hey, at least it’s free! In this tutorial we will create a simple, but effective web-stress test for an URL. JMeter is capable of doing a lot more than that, you can even test your web application’s GUI and the GUI’s results (although I recommend the much easier to use Badboy for GUI testing purposes). Here’s a screenshot of Badboy (only available for Windows):

JMeter in my opinion is perfect for stress-testing your web app, so let’s take a look at the steps to do just that:

1. Download and install jMeter from Apache’s Website here. JMeter is Java application, so it will work on a wide variety of operating systems (get the binary zip, it should work for all platforms and make sure you’re running a decent Java Virtual Machine). I recommend not to use Windows for serious stress testing of higher-end servers due to Windows’ TCP/IP concurrent connections limitations.
2. After firing up jMeter, you will be greeted by the following screen, change the name of “Test Plan” to something more meaningful.
   
3. Now add a Thread Group, which is just what it says, a group of threads, which we will use, to access our web app with simultaneous connections and thus creating the load.
   
4. After we added a Thread Group, we need to adjust it to our needs. Number of Threads specifies the amount of concurrent users. The ramp-up period specifies the period after which the full amount of users will access the web application. The loop count indicates how many cycles with those settings above should be run. In our example (50 * 10) this results in 500 users. This is a good amount to start with, it provides you with good details about your server’s performance but shouldn’t make it crash.
   
5. Let’s add an HTTP request sampler. As you can see, jMeter shows us a lot of other request sampler’s as well, like ftp, jMeter really shows, how flexible it is and that you can even stress-test ftp servers without much effort!
   
6. As we have added an HTTP request sampler, we now need to configure it. Under “server name” enter your URL (without the HTTP part). If you want to check the root folder of that URL, just enter forward slash (“/”) as the path.
   
7. The HTTP request sample is complete. We will now add a “Gaussian Random Timer” to the HTTP request. This will time the breaks between the connections in a more random fashion, so reflects the real world a lot better. Configure the Gaussian Random Timer according to the screenshot.
   
8. To see what’s happening, we need some reports! Let’s add a report with graphic visualization: Select “Graph Results”.
   
9. To see raw numbers (which is also great if you want to export your data to Excel and create your own custom reports and graphs, add “Aggregate Report”.
   
10. We’re done building our test plan. Hit Ctrl + R and run the thing! Your reports should look something like this:
    

I hope this first tutorial really gets you started with jMeter. I’m planning on posting a lot more tutorials and tips about jMeter in the near future as I get to know it better myself. If you have any questions or want to give me some feedback, go ahead and post a comment.

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Check out the screenshot below:

The projects homepage can be found here: http://phpminiadmin.sourceforge.net

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Step 1: Generate a Private Key

The first step is to create your RSA Private Key. This key is a 1024 bit RSA key which is encrypted using Triple-DES and stored in a PEM format so that it is readable as ASCII text.

Step 2: Generate a CSR (Certificate Signing Request)

Once the private key is generated a Certificate Signing Request can be generated. The CSR is then used in one of two ways. Ideally, the CSR will be sent to a Certificate Authority, such as Thawte or Verisign who will verify the identity of the requestor and issue a signed certificate. The second option is to self-sign the CSR, which will be demonstrated in the next section.

During the generation of the CSR, you will be prompted for several pieces of information. These are the X.509 attributes of the certificate. One of the prompts will be for “Common Name (e.g., YOUR name)”. It is important that this field be filled in with the fully qualified domain name of the server to be protected by SSL. If the website to be protected will be https://www.yatblog.com, then enter www.yatblog.com at this prompt. If you want to create a so called “wildcard” certificate, which means the same certificate can be used on an unlimited number of subdomains, just enter an asterisk as the hostname, in our example that would be *.yatblog.com. The command to generate the CSR is as follows:

Step 3: Remove Passphrase from Key

One unfortunate side-effect of the pass-phrased private key is that Apache will ask for the pass-phrase each time the web server is started. Obviously this is not necessarily convenient as someone will not always be around to type in the pass-phrase, such as after a reboot or crash. mod_ssl includes the ability to use an external program in place of the built-in pass-phrase dialog, however, this is not necessarily the most secure option either. It is possible to remove the Triple-DES encryption from the key, thereby no longer needing to type in a pass-phrase. If the private key is no longer encrypted, it is critical that this file only be readable by the root user! If your system is ever compromised and a third party obtains your unencrypted private key, the corresponding certificate will need to be revoked. With that being said, use the following command to remove the pass-phrase from the key:

The newly created server.key file has no passphrase in it anymore.

Step 4: Generating a Self-Signed Certificate

At this point you will need to generate a self-signed certificate because you either don’t plan on having your certificate signed by a CA, or you wish to test your new SSL implementation while the CA is signing your certificate. This temporary certificate will generate an error in the client browser to the effect that the signing certificate authority is unknown and not trusted.

To generate a temporary certificate which is good for 365 days, issue the following command:

Step 5: Installing the Private Key and Certificate

When Apache with mod_ssl is installed, it creates several directories in the Apache config directory. The location of this directory will differ depending on how Apache was compiled.

Step 6: Configuring SSL Enabled Virtual Hosts

If you want to redirect connections to the standard, unencrypted port 80, simply use the following lines:

Step 7: Restart Apache and Test

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About freeCSScart: (from its website)
Imagine the ability to make a shopping-cart look the way you want. No, not just be able change the background color of a table, but completely change the form and function of a shopping cart with a switch of your css file. Now imagine that it is utilizing 100% CSS2 and xhtml standards. Then, imagine that you could set-up and fully customize this shopping cart in a matter of hours. Finally, imagine that it was Free! This will no longer be just an object of imagination.

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People surf the web to find useful information and if they do they like to bookmark it for future reference. Now imagine the following situation: There’s an urgent problem at work, you know of a website that addresses most facets of this problem, but you can’t remember its web address (you don’t usually try to remember, because you’re bookmarking them for a reason, right?). Well, you can’t access your bookmarks right now, because they’re at home! You could, of course, export your bookmarks every now and then and import them at work, but who really remembers to do that on a regular basis? Or you could use the great Foxmarks extension for Firefox which does the process of synchronizing your bookmarks automatically for you. It doesn’t matter if you’re using Windows, MacOS X or Linux (or another UNIX-based operating system). It runs wherever Firefox runs on. You can use Foxmarks’ server to store your bookmark file on, or you can use your own server (you need an account with write permission on it). Installing and configuring Foxmarks is a breeze. Right after installing it and restarting Firefox, you will be greeted by the Foxmarks initial configuration wizard that takes care of the rest.

You can also access your bookmarks from the web if you’re on a public terminal or if there’s no way of getting Firefox installed. So there’s really no need to use online-only bookmark services anymore, since Foxmarks integrates just so well into your favorite browser and offers a superior experience.

You can download Foxmarks from the mozilla website.

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