I have been having some strange nfs problems. Our main file server, filer, has several mounts exported, serving to ~15 users. No one has any problems, except 2. Recently their computers (1 is a clone of the other) their computers will lock-up when they are nfs mounted, but work fine when they aren't. All systems are Ubuntu x86_64 on dual opteron systems, nearly all are identical. The server does not have any error messages, nor do the workstations. Does anybody have any ideas?