How do I change the IP address or hostname or both on Solaris/x86?
man sys-unconfig: Basically, sys-unconfig unconfigures the machine to make it ready to be configured again on reboot. It's a lot easier and less error prone than the usual dozen or so steps required to purge the old IP address.
Note: This appears to work on both Sparc and x86 systems
Solaris 8 FCS: sys-unconfig is seriously broken for Solaris 8 FCS (2/2000) and will make your system unbootable. If you use it make sure you have a later HW update of Solaris 8 or that you apply x86 patch 109319. Use "showrev -p" to confirm you have this patch.
For the thrill-seekers among us, you can also do it "by-hand" by editing these files (possibly more?) with your favorite editor:
Finally, use the hostname to set the hostname until the next reboot. To verify you changed all the files, type this as root: find /etc -type f -print|xargs grep `hostname`