We run a couple L700e's with fiber robot control and fiber attached drives.
We had the same problem where the robotic control was simply dropping from the SAN and none of my devices could see it. It is NOT a Veritas problem.
The Fiber interface for robotic control was a 1GB controller. STK is having problems with them ESPECIALLY if you have recently upgraded to the latest firmware levels. STK has a 2GB board they put in its place. We haven't had the problem since.