Networked ISL uses the bootp protocol. If a client machine is on a different subnet from the networked ISL server, the BOOTP gateway machine to that subnet must be able to identify the remote installation server and the client by their machine names. In addition, the installation server must be able to identify the BOOTP gateway machine by name.
The bootp protocol uses broadcast to find the server machine. Normally, broadcast is not automatically forwarded across subnet boundaries by routers. There are two possible solutions:
If the router can flag bootp protocol and pass it on, configure the router to do so. Consult the manufacturer's documentation for the router for more information.
If the router cannot flag bootp protocol, but runs on a UNIX system, use bootpgw(ADMN) (an application-level gateway for the bootp protocol):
where servername is the hostname of the installation server. This configures the gateway machine to use bootpgw.
To designate a different server for a given gateway machine, simply run netisl gateway on with the new server's name. The gateway machine stops sending bootp protocols to the previous server, and starts sending them to the new server. To reverse netisl gateway on completely, use netisl gateway off.
Once you have configured a router or gateway machine to connect the server's and client's subnets, configure the server and client for networked ISL. You will need to supply the IP address for the gateway machine.