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Configuring DHCP through a Firewall

Tom101
Level 1
Level 1

Hello,

 

How would i setup a 5505 firewall so that a router using DHCP can pass through it to assign ip addresses to devices in the inside network? 

 

My inside network consists of a 2 PCs and a L3 switch. My outside network consists of a router.

 

I have so far configured the network so that PCs that have been assigned with a static 192.168.1.x/24 address can ping the router on the outside network. This was done by setting up an object network for the 192.168.1.0 network (VLAN10) that has been assigned an inside and outside dynamic nat on the 5505 firewall, with global policy that inspect icmp packets. A series of ip routes were added to the router, firewall and L3 switch so that the packets can reach other. 

 

I'm having trouble allowing the router DHCP configuration for VLAN10 to pass through the firewall so that the inside PCs can get assigned a static ip address. I'm not even sure if this is possible on packet tracer - does anyone know?

 

Attached to this post are a few screenshots and the packet tracer to help understand what's going on - i do apologies, i'm not so good at explaining it. 

 

4 Replies 4

Hello

Easiest solution would to apply the dhcp server on the Layer 3 switch, Given the restriction on the PT ASA regards dhcpd.
Please review working attached PT file.


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

Hi

  Find attached a file working with the DHCP server on the router and passing through the firewall.

Any doubt, let me know.

 

Hello @Flavio Miranda 
Curious as to why you’ve appended the dhcp service on the rtr, which is external to the firewall (untrusted) and then obviously the lan subnet, Wouldn’t it be more applicable to either append it to the Fw (which in PT is limited) or on the L3 switch?


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

you are correct this is the wrong way to guide the member. this should be stop guidance should be professional.

 

if members ask questions in the wrong way our responsibility is to correct them and give a direction.

 

 

 

Thanks,

Jitendra

Thanks,
Jitendra
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