Brodcast Domains and Routing - Simple question

[dan_track]

Hi

Can someone please tell me is it possible to route/forward broadcasts to other vlans?

Thanks

Dan

[Collin Clark]

Dan-

Yes it is configurable. If you let us know what you're trying to achieve we can give more specific details/config.

[dan_track]

Great,

I've got an application that is broadcasting on vlan 10 I want to forward those broadcasts to vlan 24 only. What do I need to do to get that going?

Thanks

Dan

[Collin Clark]

You can use the following command to forward broadcasts from vlan 101 to a specific host on vlan 24.

interface vlan 101

ip helper-address [address on vlan 24]

[dan_track]

Great,

Thanks for that. How would that affect my dhcp assignement? Won't the machines lose that ability?

Thanks

Dan

[Collin Clark]

Good point. The switch processes the helpers in order, so if you put the application first, it forward to the application. In DHCP it will also forward to the application for an address, but it will never get one so it well then query the next helper and request an IP. Does your broadcast use a particular port? We can forward on a custom UDP broadcast port if it uses one.

[manderson2]

I know of two ways:

ip helper-address (to forward netbios)

or

multicast (PIM) also can be used

Mike