Last week I posted this thread about some VLAN woes I was having and a few of the members here were extremely helpful. Now I am hoping someone can help me in the next step of troubleshooting this absolute dumpsterfire.
Here is a simplified topology that will help illustrate the situation
I have multiple VLANs with ip routing enabled on the layer 3 switch. Right now I am chiefly concerned with VLANs 1 and 22. There is a DHCP server on VLAN 1 with a /23 subnet. When I plug a device in on VLAN 1 it gets DHCP no problem. I would like it to be able to also serve DHCP on the VLAN 22 subnet so I edited the dhcpd.conf file on the DHCP server to include a second pool that matches the VLAN 22 subnet.
When I plug my laptop into a VLAN 22 access port on a layer 2 switch that is trunked to the core I am able to set a static IP in the laptop and ping the VLAN 22 gateway, get internet, etc. I am also able to ping the DHCP server on VLAN 1 no problem. However, I when I tell the same laptop to obtain it's IP address automatically I get no IP.
The DHCP server has subnets on it for both the ip pools in VLAN 1 and VLAN 22 but it will only serve DHCP to the devices on it's same VLAN (1). How can I get this to work? What is stopping the DHCP server from serving IPs to a different VLAN?
I noticed VLAN 1 has "no ip proxy-arp" on it. Is that the reason?
I looked at the ACL on the core switch and I don't see anything about denying UDP between the subnets so shouldn't DHCP work between them?
I have a feeling I may be going wrong somewhere on a more fundamental level. Maybe I am misunderstanding how DHCP works. Any help would be greatly appreciated.
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