Isilon OneFS 18.104.22.168, lsassd has a memory leak. Upgraded to 22.214.171.124 fixed memory leak and also supposed to emulate support for extended attributes.
Interesting: running top from SSH console of machine showed lsassd process grow over a period of a few hours. Isilon has another process that checks for any processes taking up over 512MB memory and kills them.
In this case, that disconnected all my SecureCopy sessions.