Issue with Cisco L3 switch with multiple DHCP scopes.

VLAN 1
DHCP Scope 10.15.2.0

VLAN 8
DHCP Scope 10.15.8.0

All the ports on the switch are in VLAN1, but I am getting some PCs getting an IP from VLAN 8. How is this possible?

I did notice that the VLAN interface does not have an IP assigned to it, would this cause an issue?

I thought that a PC would have to be in the same VLAN because DHCP is based on broadcasts.

What could cause this?

No one has problably replied because what you are describing shouldn't be happening. You are correct, if the switch port is in a particular VLAN then it will be sgemented at layer 2 from all other VLAN ports.

Hmm, can you do a packet capture ?

I would also double check the VLAN configuration.

I'd first double check the VLAN config as Smurf suggested.

What DHCP server(s) are you using? is it a router or a Win/linux box?. If the later, then make sure the DHCP server for VLAN8 is connected to a VLAN8 port on the switch. If your using a router as your DHCP server (i.e router on a stick for both VLANs), then I'd double check the masks set for the two scopes/pools (apparently /24 in your case).

Still no hope? Then what happens when you set one of those ports to VLAN8, does the PC connected get a VLAN8 IP or a VLAN1 IP?

Sorry, I didn't make myself clear. The DHCP is given from the Cisco switch itself.

Never mind, A post of your config could help.