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3550/2950 DHCP relay option to Router handing out DHCP

Have a client wanting to hand out public ip addresses to all clients from a PFSense Firewall terminating the internet connection.

How do I allow the Cisco Switches currently in place, configured with private ip addresses in the 10.10.x.x ranges and Vlans, where the main 3550 layer 3 has defined dhcp scopes for each vlan, to relay dhcp requests from all vlans to the PFSense firewall?

I assume I would take off the currently defined dhcp scopes for the vlans and configure each vlan/switch with the ip helper address and specify the PFSense firewall and that Nat would have to be disabled onthe firewall?

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3550/2950 DHCP relay option to Router handing out DHCP

Is the firewall handing out IP addresses or is the 3550 L3 switch configured to server DHCP request?


If the firewall hands out the DHCP addresses and the clients are on the inside, you will need to add IP Helper (IP) statements on each vlan so the L3 switch will know where to forward the clients DHCP requests.




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