Here is something you may not know, I know I was not aware. FICON is only supported in specific versions of SAN-OS / NX-OS. So you may see all kinds of strange behavior, as I have been seeing and reported here and Cisco may not be able to assist you if you are not running a FICON supported release. This is documented in the release notes. Here is a summary of the supported releases:
|FICON Supported Releases|
|NX-OS||Release 4.2(1b)Release 4.1(1c)|
Just something to keep in mind if you do see weird stuff going on when working with FICON and also very important to keep in mind when looking to deploy FICON in production.