[K12OSN] Logons get slower with time with Active Directory/pam_mount (fwd)

[Tom Wolfe]

This isn't /quite/ a repost, I've made a little progress -- but someone
out there must know an answer!

As the day progresses, logons get slower (by the end of the day up to a
minute long). We have Active Directory authentication and pam_mount to a
windows server for the students' document folders. When I run df I get a
huge list of open share mounts, mostly from inactive users (users that
have probably had their logons interrupted instead of logging off). When I
run umount -a things speed up again.

Does anyone know how to fix this in a more elegant fashion, i.e. is there
any way to unmount shares for inactive users?

Thanks,
Tom Wolfe