asterisk users - Jun 2005 - How to setup two Asterisk boxes - keeping the registration

I have now two asterisk boxes running, one on the IP *18 and one on IP *20

Both are working, use the same dialplan and realtime.

I did not find out how to set it up that if a phone is registered in *18 
can reach a phone registered in *20.

For the wake up call I also see some troubles, since both machines point 
to the same NFS space. It could be that both machines start the wakeup call.

Has anybody solved that?


bye

Ronald