Chris Connell, from the UK, recently posted this korn shell script on BigAdmin:
http://www.sun.com/bigadmin/scripts/submittedScripts/hotlink.sh.txt
It checks the speed and duplex settings, plus the health and vlan information for network interfaces on a Solaris system..
To get MAC address output you need to run it as root.
He did not use ARP output because it could affect the performance of a live system.
- Rick
BigAdmin blog
Belly Button Lint blog