Infrastructure Software

This may not be the toughest question of the day, but it's been a long
time since I've tinkered with our SunOS 5.5.1 machines:

I have a mixed network of Sun and Windows machines, with both a Sun
server and a Windows NT server. They all use the IP range of
192.9.200.xxx. I am installing a new Windows 2000 server and want to
change over to a new IP range, 192.168.20.xxx.

I've got the new server running on the new range alongside the old
server on the old range.

When I do the conversion, I'm going to go around to the windows
(NT/2000/XP) boxes and give them new IP addresses (192.168.20.1, .2,
.3, etc). There are about 20 machines, no big deal.

The problem is the Unix network and the Windows network share
printers, so the Sun boxes need new IPs as well. Unless, of course, I
multi-home the adapters on the Windows machines, but I've noticed
terrible performance when I've done that before.

How do I change the IP address of the Sun box? Do I only have to edit
the /etc/hosts file? Or is there something else I need to change too?

Any and all thoughts appreciated.

Regards
Peter Brown