02-04-2011 03:18 AM
follow the recommendation of your support vendor. Choose the FOS code which you would like to install. read carefully the release notes to avoid any issues during the update procedure.
Read this document from Brocade:
Remember since FOS 6.0 you have to install each major version. No jumps are allow. 6.0 --> 6.1.x --> 6.2.x-->6.3.x --> 6.4.x
I hope this helps. Please mark this thread as answered if not let me know.
You can find some more threads with useful information about FOS updates.