Full DHCP relay setup of VLAN

[Bas S.]

Hi,

I'll admit right off the bat, it's been years since I've done anything with Cisco devices (which wasn't much to begin with), so I'm stumbling in the dark a little. Help would be greatly appreciated. I'm currently in the process of setting up a new IT infra for our company, as we're separating from our previous parent company. To do so, I've got 4 Catalyst 2960-X switches to connect all the clients to the core switches. I'm currently setting everything up in the building we're currently housed. The IT department of our previous parent has graciously allowed me access to the server rooms and all that. They (and I) prefer to do an in-place replacement of the current systems, before we move to our new building and sever ties. 

At the moment, all I have in terms of networking equipment are the 2960's (plus my 10Gbit switches, but those aren't in scope at the moment). I don't have my own DHCP yet (my servers are still being delivered), and also my firewalls (which could temporarily function as DHCP are running late due to deliverability problems. I want to configure one of them to temporarily set up my network storage devices. The IT guys told me to "just configure the switch to use DHCP", but I keep running into problems.

I'm supposed to configure a VLAN with the following parameters, using the currently allocated VLAN in their setup:

• DHCP server: 172.25.0.5
• Current VLAN: 172.25.120.x
• I've got no reserved IPs in the DHCP range

What I've tried so far is configuring a vlan with

ip address dhcp

ip helper-address 172.25.0.5

I've configured one port as trunk and assigned it to the vlan, assigned several others to the vlan in access mode. I see packets being sent and transmitted on the trunk port, also on the access port, yet none on the clients that connect (several laptops).

I'm sort of lost here. I've been at it for a day now and keep ending up resetting my switch because it simply doesn't work. Is anyone willing and able to help me achieve the simplest possible config to achieve this? If you need more information, I'll gladly provide it.

Thanks in advance,

Bas

[Dennis Mink]

Can you actually ping the 172.25.0.5 ip address from you 172.25.120.0 subnet?

also what is that 172.25.0.5?  like a separate DHCP server?

Please rate if helpful

[Bas S.]

Not behind or on the switch. I can reach it when not connected to this switch.

172.25.0.5 is the primary Windows DHCP servers in the network.

[Dennis Mink]

Bas,

remove the ip helper statement and create a dhcp pool on the switch itself.

there is plenty of documentation on how to do this.  make sure you connect to the switch with a static IP and see if you can actually ping the switch IP address no point proceeding if you cant ping.

please rate if helpful