IP helper-address not working

[Michael Durham]

First let me say that I feel dumb for having to ask for help at such a basic level.  I had this working a few weeks ago on different routers and switches.  But after spending 3/4 of the day trying r solve the problem, I am seeking your help.

I am studying for my CCNA Voice using Jeremy's nuggets.  The very first lab is basic, two switches and two routers.  Attached is a pdf file showing the network design.  The second file attached is a Word 2007 document that has the config files for each item.

I have 2 Vlans, 20 = Voice and 30 = Data.  The CME/TFTP router has two IP addresses, vlan 20 = 172.16.1.1 and vlan 30 is 172.16.2.1.  The second router is the DHCP router which is IP 172.16.2.5. The CME router can ping the DHCP router. The DHCP router can ping 172.16.2.1 but not 172.16.1.1.

Swtich A can ping  172.16.1.1 and 172.16.2.1 but not 172.16.2.5

Switch B can ping 172.16.1.1, 172.16.2.1 AND 172.16.2.5

Phones in Vlan 20 do not get an IP address at all. I also put a laptop into Vlan 20 and it does not get and IP address.  When I manuall assign an IP to the laptop in Vlan 20, I can ping 172.16.1.1 and 172.16.2.1 but not 172.16.2.5

PC in Vlan 30 get an IP address and can ping 172.16.1.1, 172.16.2.1 and 172.16.2.5

What do I need to do so that the phones get their IP address in Vlan 20?

[pjmonline]

I see a few things I would try.

On dhcp router the IP address is on the physical interface which is by default vlan 1. I would try putting the IP address on a sub interface for vlan 30. Int fe 0/0.30

The other thing is that you ha e eigrp is setup on switches but not routers. I would add that to the routers so they know about the other networks.

Sent from Cisco Technical Support iPhone App

[cadet alain · Accepted solution]

Hi,

your DHCP server has got no route to 172.16.1.0/24 network so it can't lease a dhcp address in this subnet and it can't reply back to pings from this subnet.

just add a static route for this subnet pointing to g0/1.30 IP address on the RoAs router.

Regards.

Alain

Don't forget to rate helpful posts.

[Michael Durham]

Thank you so much.  I can't believe that I missed that.  When you look at something so long, you become blind.You guys are AWESOME!!!!

Michael