10/2/2002 -- If you're serious about getting Citrix's Certified Enterprise Administrator (CCEA) title, I strongly recommend that you take the company's NFuse Classic Administration exam (#951) as one of your requirements. As you probably know, NFuse is an application delivery mechanism that "Webifies" applications for access through the Internet using a Web browser. NFuse is probably the most sought after Citrix technology today because of its ease of use: Using NFuse, you can make applications available via the Web without writing a single line of code. As one of the main add-ons to MetaFrame XP, it helps tips the balance in Citrix's favor when selecting between Microsoft's native Terminal Server and Citrix MetaFrame XP (perhaps this point is debatable for some, but you really can't ignore Citrix when you're thinking about going thin).

If you're already working with NFuse, you're probably wondering exactly how hard the NFuse exam could really be. After all, you're an NFuse expert - can't you just to walk in and take it? Well, that's what I thought when I signed up for this exam, and exactly one minute into the test I got my wake up call. This is one of the most surprising CCEA exams. Sure, you know how to install NFuse and make it work, but do you understand how NFuse functions? Do you really know exactly what each file does and which file is called on first? Are you absolutely certain you know the contents of that file?

Because I underestimated the exam, I under-prepared -- I simply browsed through a CramSession.com study guide for this exam, thinking the whole time, "Yeah, yeah, I know all this." As a result, I spent most of the exam trying to avoid the embarrassment of failing. Turns out that I passed, but I offer you these 10 tips so that you won't walk in and be caught off guard like I was.

Tip #1: Know the Nuts & Bolts of NFuse
Citrix makes a point to test its candidates on their knowledge of the architecture of the technology they are aiming to be certified in. For this reason, make sure you know exactly how NFuse works -- from the minute the user accesses the NFuse portal, to how the request travels, to which ports it crosses, to what's needed on the client to access NFuse and launch an application. In a nutshell, expect anything and everything that has to do with how NFuse operates.

As with every other exam, knowing the basic definitions and terminology of the main features and core architecture is crucial. For example, be sure to familiarize yourself with the differences between the server applications and the published applications, as well as the difference between publishing an application in an NT Domain scope and a farm scope.

Tip #2: Become an Installation Guru
Be sure you actually install NFuse several times before you try and take this exam. While you're doing it, pay close attention to the options you get at every step of the installation. This is a good method for becoming familiar with the file that should be run to setup NFuse on IIS or on a UNIX platform. And in order to make it work, you'll also need to install or configure the Citrix servers in your farm appropriately and, of course, properly configure the client device accessing these applications. By doing all of this and getting it to work, you'll have covered 40 percent of the exam.

With the release of MetaFrame XP, be sure that you also install NFuse to support a MetaFrame XP server and then compare the differences, especially in the approaches to the XML port. The XML service and its related port are an integral part of NFuse, so don't walk into this exam without knowing how to configure the port and how to change that port later on if necessary. Different feature releases of MetaFrame 1.8 address this issue, so get familiar with what each FR level introduces with regards to the XML port in particular, as well as the features in general.

Tip #3: Dig into the ICA File
The template.ica file contains parameters and tags that you should understand and be able to read. You need to know what every parameter does and how to tweak it. This information is useful for the exam and downright necessity when troubleshooting real-world problem. Be sure you understand what's in the ICA file and what isn't. Extra Tip: Some of you are probably familiar with launch.ica. This file is copied off of template.ica, meaning that if you open template.ica in notepad and make changes to it, the changes will be reflected the next time someone launches a particular application.

Tip #4: Know the Website Wizard
The Website Wizard has been discontinued as of NFuse 1.60. However, since the exam is currently testing you on NFuse 1.51, you need to study it anyway. Know what it can do. Within the wizard, you can enable or disable Ticketing, choose the layout or color schemes for your site, configure Authentication and select a Citrix server in the farm. As always, the best way to learn the capabilities is hands-on practice, so be sure to play around with the Website Wizard until you're comfortable with every step, know what each one offers, and have the default settings down cold.

Tip #5: NFuse Tags
NFuse tags - be it substitution, session fields, application property, user interface or conditional tags - are something you need to know as a certified NFuse expert. Yes, I know, you're probably thinking, "Is this guy nuts? Does he really expect me to memorize all these tags?" Well, no, but you should at the very least have an idea about the naming convention of each of the tags (for example, NFuse substitution tags all start with NFuse_). By understanding the naming conventions and getting familiar with all of them, you should be able to tell when a tag you're presented with isn't valid.

Tip #6: What's That Called Again?
Yeah, you're an expert. But which file is used to setup the IIS extensions on IIS? You don't know? As I stated earlier in this article, this is where this exam gets tricky, even if you're experienced in working with the product. To be well prepared, you should be able to identify the correct files names for the set up and configuration files. Sure, you can browse and figure it out in the real world, but I think Citrix wants to make sure that anyone who passes their exam really knows their stuff, and figures that experience professionals who have done it numerous times will know the file names without really thinking about it.

Tip #7: File Guidance
T are several files that are called upon when a user logs into the portal and launches an application, and you're going to need to know them inside and out. The files include: Default.htm, Icaclient.asp, Login.htm, Passthrutemplates.asp, Boilerplate.asp, Blank.htm, Applist.htm, Template.ica. Which file is called first? What order are they called in? What does each do? What does it carry or store in terms of information? I wasn't kidding when I said earlier that in-depth knowledge of NFuse's architecture is required to pass this exam.

Tip #8: Which Web Server Can I Use?
As with every other certification exam, one of the "givens" is what kind of OS can the program run on, and this NFuse exam is no different. NFuse has a wide variety of Web servers that it can run on. If you want to pass this exam, you need to know this. And while it's easy to memorize the platforms it supports in the Windows world; it gets harder with Unix because of the many different flavors. Be sure to review the different OS vendors and versions NFuse is compatible with.

Tip #9: Know the Ports
No NFuse implementation is complete without opening up the correct ports on your firewall. Failing to open up these ports limits NFuse use to users behind your firewall, defeating what makes NFuse so attractive -- the ability to access applications from anywhere with an internet connection and a supported Web browser.
Be sure to familiarize yourself with each port number and what it does (and what happens if its not opened). For example, Port 1494 allows you to connect to Published Applications; if this port is blocked, users (again, outside the firewall) can't launch applications. Port 80 is HTTP port (if you didn't know that, don't plan to take this exam). Also, don't forget that when setting up the XML port on the Citrix servers, the port is set to 80 by default. If, for security reasons, you've changed that port, you need to accommodate this change within the application's port settings to allow proper communication between the NFuse Web server and the Citrix servers in the farm.

Tip #10: Security and Encryption
Security is an important topic on this exam (as in life), so don't neglect to study what kind of security NFuse supports and what kind of client goes with that security. Be sure you know your security options and your encryption levels and options. Again, while it's great to know for this information for the exam, where it really comes in handy is on-the-job.

Sure, There's More…
…but there's only so much one can cover within 10 tips. I hope this gives you a better idea of what to expect when you walk into the exam -- especially the idea that even a little preparation can really help your test score, even if you already are an NFuse guru.

Questions? Comments? Tips of your own to share? Post your thoughts below!