How to reload /net "maps"

[Greg Wooledge <wooledg@eeg.ccf.org>]

Debian 5.0, autofs 4.1.4, kernel 2.6.26-2-686

I may be overlooking some documentation, but I couldn't find out how to
do this.  Occasionally one of our NFS servers adds a new entry to its
/etc/exports file, and we'd like the clients to be able to use it.

The clients look like:

# grep -v '^#' /etc/auto.master
/net    /etc/auto.net

At some point in the past, autofs will have contacted this host and
somehow "cached" the fact that it was sharing /home, /data, etc.
Now I've added /opt to the exports file.  But when I do "ls /net/servername"
I still only see home and data, not opt.

Rebooting the client works -- after a reboot, I can see home, data and opt.

I'm trying to find a way to get autofs to reload the server's list of
shared file systems without totally rebooting the client.  If I issue
a "/etc/init.d/autofs reload" command, I get a few normal-looking messages,
but no change in the list of results.  If I try "/etc/init.d/autofs restart"
it tell me it cannot stop the /net daemon, and cannot start a new one.
Manually attempting "kill PID" or "kill -HUP PID" has no visible effect.