Migration: Planning and choosing
My agency has a small IT budget, and our IT members aren't friends of Windows. We reached a point where we wanted to get rid of Windows NT. We had a read lot of news about e-goverment with open source tools and Linux. So, we decided to migrate our database (the application was created with PowerBuilder v. 8.0 using Sybase 8.0.1 as the data repository) to Red Hat Linux 8.0. We have a register with very special data (about law enforcement) and many custom reports. Everything was fine until we tried with some custom (and mission-critical) applications on Linux. The apps run with Sybase 8.0.1 in almost 40 locations around the country. We could not resolve the dll's references made by Sybase on Cygwin. Sybase asked for many resources (like dlls), and some of them we just didn't know about. Without those dlls, the application didn't run.
We tried with everything we found, including cygwin, but all failed, and did not run. So, we gave up. Now, we are trying to decide whether to migrate to Oracle 9i and Linux or to Sybase 9.0 and Windows 2000.
My questions are: What could we have done differently in our first migration try? What is your advice about how to evaluate our options so that we won't have another failure?
Ah...it's always the custom stuff that kills you. I'm wondering if you've thought about rewriting the custom reports in your first attempt to migrate off
the Windows platform. I know people that spend weeks trying to convert something, where if they did the same things from scratch it could take days or
hours. Not looking at your plan, I really won't be able to tell you exactly what you did wrong, or what I would have done. What I can tell is that the
assessment part of the project is the single most important component of any successful migration. You need to document possible
thing you have
before you set about your implementation plan.
Please keep an eye out for my upcoming tips on Linux/Unix migrations, which may have some more detail regarding specifics that you are looking for.
Regarding migration choices, if you're looking for systems that will scale better in an enterprise environment (not to mention perform better and be
more reliable), please choose the Oracle/Linux solution. Of all the many types of platforms you can pick, there may be no other platform that has as
many success stories as Oracle/Linux. Start with this URL:
(http://otn.oracle.com/tech/linux/index.html) and do your own research as well.
This was first published in April 2004