I am working with an installation of Solaris 10 on a VMWare virtual machine. After the initial installation, the system was indicating that the nodename was unknown. Additionally, the network configuration is not configured properly yet, so the server is not able to reach the DHCP host for hostname assignment. To fix this issue, I had to do a little poking around. I asked my good friend Mr. Google, and that turned up a blog called markwilson.it, and an entry about the issue which points me to the Sun Developers Network post on the issue.
The short solution is that you must create a file called “nodename” (no extenstion) in the /etc directory. Inside the file, insert one line with the nodename you would like to use. Reboot.
Additional assistance for configuring Solaris 10 DHCP client to register with a Microsoft DNS is found on the same blog. See also, SUN’s instructions for the Solaris 10 DHCP to DNS configuration.