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Cisco networking

By jpwhite ·
I have one network already set up. It is in the ip scheme of All of the devices on this network are statically assigned. They are plugged into an unmanaged switch behind a cheap linksys router and then plugged into a dsl modem to gain internet access. This IP scheme almost definitely cannot change at this point.I am setting up a backbone right now with fiber that will all be tied together with managed 3com switches. This IP scheme will be - This network will have a separate windows server that will be a domain controller, dhcp controller. I want to replace the linksys with a cisco router and link these two networks together. Is there a way of preventing dhcp from traversing across router ports. I don't want dhcp on the network however I want to be able to access devices from to Is this possible?

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IP Forwarding / Helper -address

by valavan In reply to Cisco networking

There are basically two commands you need to
look at "ip forward-protocol" and "ip helper-
address". If you want the
segment to access Windows DHCP, you can use
the command "ip helper-address <DHCP IP-
address>" on the LAN interface. This will
forward DHCP requests to Windows segment.

If you want to completely block DHCP
forwarding , use the "no ip forward-protocol
53" command , which will block DHCP from
Windows segment reaching the 192.168 segment.

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