ip helper address

[kcountway]

To forward a udp broadcast to a remote subnet, what do I configure for a helper addr? For example if the remote subnet has a router interface addr of 192.168.100.1/30 do I use ip helper-address 192.168.100.0 or 192.168.100.3 or the router interface?

[thisisshanky]

Your helper address should be either directed to a broadcast or to a unicast address.

The broadcast address for your subnet is 192.168.100.3. If you have a server on that subnet which is supposedly receiving this broadcast, say 192.168.100.2/30, then you can even forward your udp broadcasts to that.

[kcountway]

thanks, that sounds like the classical way of doing it. i just started a new job a few months ago and this company does it using the network address, In my example 192.168.100.0. Seemed like a strange way to do it and i'm wondering if there is a reason? It apparently has the same effect. No one here seems to have been involved with the original decision to do it this way vs using the b'cast addr.