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New Member

Blocking un-necessery UDP traffic when using IP helper address

Hi ,

My branch office network with workstations is contacting my DHCP server in datacenter across a T1 link for getting their IP addresses.I've enabled forwarding of DHCP request from client network router using IP helper address.

By default when i use IP helper address command some eight protocol traffic gets forwarded ..right?

Is there a way to block a few of them which are not required? Is the solution access list at router or a command associated with IP helper address which disables some port from the list of eight.

When i use IP helper address pointing to a particular host does the router carry the broadcast to only that single host or to the entire network in which the host sits?

Thanks and Regards,


New Member

Re: Blocking un-necessery UDP traffic when using IP helper addre

In reverse order:

If you specify a host address, thats where the request gets forwarded. You can alternatively use the broadcast address for that subnet.

You need to override the default by issuing:

'no ip forward-protocol udp nnn'

from global config.

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