- It is incredibly expensive. Just getting a baseline iSeries with a single CPU, 2GB RAM and 150GB storage is going to run you over $20K. In my case upgrading from 1GB RAM to 4GB and 5 drives to 8 drives was going to cost over $10K. This was in addition to the $40K we had already paid for the box.
- OS/400 an arcane beast and finding good information is extremely difficult. I have a cursory understanding of how it fits together, but after eight years working with it I'm still mostly clueless! It just runs, which is good, but when there are problems I haven't the foggiest idea where to go to figure out what is going on. I end up spending lots of time on the phone with IBM support. They're good, but I would really appreciate something a little more approachable with better documentation.
- Upgrading was a pain. Each release of Domino came with it a list of the patches you had to have on your iSeries, as well as what version of OS/400 you needed. Verifying the patches was a tedious process, installing new ones took even longer, and heaven forbid you actually had to get an OS upgrade to install Domino. Domino 7 requires i5/OS 5.3, which our iSeries won't support, so we could not upgrade to Domino 7.
- IBM doesn't seem to know what to do with the AS/400 / iSeries / System i5. They keep renaming, rebranding and remarketing it. The latest push has been to use the iSeries to run linux. I just don't see that IBM is really moving the platform forward.
The decision for the migration has been made, the new hardware has been purchased, and I'm in the process of doing my migration. This is just an explanation of the reasoning that led to the decision.