So the problem is we have a device or host that needs to communicate on a specific VLAN. This VLAN is not new, it is running all throughout our environment and works fine. But the VLAN was recently configured on the switch in question, a Cisco 3750. The DHCP server is handing out addresses on that VLAN with no problem.

I have verified the cable between the host and switch and tried multiple hosts, but none of them can communicate or get an address. I plugged my laptop into an empty port which had a different VLAN assigned and immediately got a DHCP address. When I changed that port to the same VLAN I'm having issues with I got the same problem. The laptop just sits there and tries to DHCP an address but nothing happens.

I double checked the cores and their Layer 3 VLAN config and its fine too. Plus I figured the issue couldn't be with them because the VLAN works fine everywhere else it exists.

So the only other thing I can think of is the switch, but the VLAN exists on the switch and seems to be configured correctly. The trunks appear to be configured just fine as well too.

Anyone have any ideas? I'm lost on this one.