The extensibility of FIM has always been one of its great features – allowing us to tailor it to suit the specific needs of the environment. But don’t get carried away!
If you’re going to be doing any development for FIM keep track of exactly what is and is not “supported”. I will always avoid implementing anything that is explicitly “unsupported” in a customer site as these are things that may easily be broken by hotfixes and upgrades, no matter how well they worked when you first put them in.
There is also the grey area of “not documented” that I’m starting to become wary of. When I first started working with MIIS there wasn’t a great deal of documentation so you did what worked. However I’ve now had a few experiences with FIM updates that have broken things which, while not explicitly “unsupported”, were also not documented.
While we might sometimes struggle with limitations of FIM in various areas, you have to hand it the product group for ensuring that all supported, documented functionality continues to work through upgrades. This even includes 32bit rules extensions written for MIIS 2003 which, as long as they stayed within the documented parameters, will continue to work unchanged on FIM 2010.
Got something to add? Disagree? Comments are open!