Yes, if you want to be able to retreive
all the information for that subnet. This is not really a limitation of OpenAudit, but is a limitation of TCP/IP.
You can run the nmap application and the openaudit nmap scripts from a remote subnet, but the results will be incomplete (see the documentation at
http://nmap.org/ for more details), and therefore not really worth the effort.
Far better to run a copy of the nmap script on each subnet from a local machine on that subnet. This could be a windows box using the nmap.vbs script, or a linux box using nmap_linux.sh
The main Windows PC auditing script (audit.vbs) relies on WMI and can be run across subnets with no issues, providing it can access WMI through any firewalls, and has sufficient local permissions to audit the machines.
Hope this helps.
Andrew.