Web Structure and Infrastructure

The triumphs, trials, and tribulations of running a Web site

Like many Web masters, I'm not a systems or network specialist. I have no formal training or extensive experience in either area. I'm strictly responsible for managing the development and production of Windows NT Magazine's Web sites. Because of the Web technology group's ever-growing needs, short development timelines, and a need to address problems quickly, my group has become responsible for its own tech support. This added responsibility can be taxing at times and takes away from what we are supposed to be doing. However, tech support also keeps us current on system configuration issues. The best partabout providing our tech support is that we can limit access to the Web servers.Because our IS department doesn't support our machines, IS can't access them.The whole situation is a Catch 22--we can limit access to the machines, whichmakes security easier, but we also have to support them. I imagine the Webtechnology group will soon have a support mechanism instead of the developmentteam having to support itself.

In terms of tech support, the biggest trouble area has been selecting theproper hardware and software for hosting our Web site. We've switched Web serversoftware and hardware several times during the past two years. Some of thesechanges resulted in dramatic improvements; others had the same effect as openinga can of worms.

The Right Hardware and Software
Did you know you can have too much horsepower in your hardware? When Iupgraded our single Pentium Pro 200 Web server to a quad Pentium Pro 200machine, the Windows NT Magazine Lab, which does all sorts ofperformance and scalability testing, tried to warn me that I might bedisappointed. We were going to launch the Windows NT Solutions Directory, and Iwanted to start gearing up for it.

Initially, we set up the quad Pentium Pro machine to run InternetInformation Server (IIS) and SQL Server--we were quickly disappointed. Sometesting showed that this configuration worked well, but when we put it underheavy load, it choked. Too many processes were competing for the same resources.So we went back to running the Web site from the single Pentium Pro 200 machineand moved the SQL Server to a separate dual Pentium 100 machine. Thisconfiguration didn't run circles around the quad Pentium Pro 200 machine inperformance, but it was stable.

After a lot of testing, tweaking, and shuffling, we ended up with a quadPentium Pro 200 with 256MB of RAM for the Web server and a quad Pentium Pro 200with 512MB of RAM for the SQL Server. Of the two, the database server runningSQL Server 6.5 has been magical. No matter what type of Web testing we doagainst other Web servers, this machine screams. It concentrates on one thing,providing database access, and it performs this task very, very well. For theSQL Server, I wouldn't want any other system.

Besides using the right system, configuring it with lots of RAM helps.Added RAM is nice for performance when you can get your applications to use it.However, 512MB is painful when you have to reboot your live machine and waitthrough the memory test. Unfortunately, our servers do not let us escape thetest, so we have to wait for the machine to verify all the memory.

The Web server has been a different story. Our Web server hosts severalapplications, unlike the SQL Server, which provides only one service. Our Webserver hosts IIS 3.0, Cold Fusion 3.0, AdJuggler, and IIS Assistant (IISA). Thatlist might not sound like much (or to some readers it might sound like toomuch), but a lot is happening here. IISA and AdJuggler have never causedproblems in terms of performance or stability, but IIS and Cold Fusion havetheir moments. When IIS dies, everything stops, and when Cold Fusion stops, morethan 80 percent of the site becomes unavailable. When you start consideringvirtual servers, more than just one Web site is at risk--if one is down, they'reall down.

We haven't seen an astronomical increase in performance with the quadPentium Pro Web server, so I'd rather have several less-powerful machines thanone all-powerful machine. In fact, because of recent performance problems, Imoved the Web forums off the main Web server onto a separate machine. The forumsserver still accesses the same SQL Server, but I've distributed the Web serverprocesses for better performance. The best part is that the forums applicationwent from being sluggish and almost unusable to being a speed demon. Moving theforums to their own server also increased performance on the main Web server.

By distributing various Web applications over different servers, I'velearned that I can better tune and troubleshoot the applications. If I had ourconfiguration to do over again, I would have each Web site running on a separatesingle or dual Pentium Pro server instead of one quad Pentium Pro Web server.Not very efficient or cost effective, but such a configuration would makepinpointing problems easier because you don't have everything running on onemachine. Distributing sites and applications lets you find the squeaky wheelwhen you have a problem. For the cost of the quad Pentium Pros, I could havepurchased and configured three dual Pentium Pro machines.

This configuration won't work for everybody, but at least you can get asense for some options you need to consider when selecting your hardware. Baseyour selection on what you think your current needs are and what you think theywill be in 6 to 12 months.

The fact that so many IIS benchmarks are done on dual Pentium Pro machines,and the fact that I don't think I am even touching my quad Pentium Pro machinegave me a great idea for next month's column. I am going to do a series ofperformance tests on different hardware configurations. I will be pitting a dualPentium Pro 200 against a quad Pentium Pro 200. At the time of this writing, Ihaven't determined what set of tests I will use. Nonetheless, I plan to let youknow what you can expect with these different setups. The initial round of testswill use IIS 3.0, and we will see whether IIS 4.0 makes it into the picture.

Personal preferences really come into play when you begin selecting thesoftware you use to deliver your information. Personally, I've gone from one Webserver application to another, then back to the first, and then back to theother. We currently use IIS 3.0, and I'm anxiously awaiting IIS 4.0. As Imentioned last month, I like the direction Microsoft is taking with thisproduct. And if the company continues to make the product available for free asit has with the other versions of IIS, then the decision to use IIS is eveneasier. But because this topic can quickly turn into a bias-for or bias-againstdiscussion, I will let you look at the different features and prices and come toyour own conclusion.

Planning
The best thing you can do for your Web site is to plan it out. You need todecide which individuals are responsible for each part of your site. Changingthe character of a Web site is easy, but changing or redirecting people andmethods is not. You need to establish your Web site's goals, direction, andresponsibilities, keeping everyone involved in mind. This task is easier to donow than it was even two years ago because people are more aware of what the Webis and what it can do for them.

I hope this month's column has given you food for thought. Just rememberthat buying the biggest, baddest machine around won't necessarily provide youwith the ultimate Web environment. Consider your needs and weigh the options.Next month, I will show you how much of an advantage a multiprocessor machinecan give you in the Web arena.