Is it possible for DHCP to operate through a no switch interface?

[Tom101]

I'm trying to setup a DHCP server that's configuring two VLANs on Cisco Packet Tracer through a port with no switchport.

I have attached a screenshot and a Cisco Packet Tracer file for reference and to help explain my problem. 

My main problem is that device named L3Switch01 needs to be on a different subnet than the L2Switch01 and the DHCP server. In order for the L2Switch01 and L3Switch01 devices to communicate i have given L3Switch01's FA0/1 the ip address 10.10.10.3.

So, my question is, is it possible for a DHCP server that uses VLANs to operate over an interface that's configured with no switchport, or in order for it to work does it have to be a trunk port? 

Would anybody be able to help explain how this network could be configured, so that the L3Switch01 is on a different sub network?

on the L3Switch01 each VLAN has been given an ip address of the vlan's default gateway and an ip helper address that points to the DHCP server.

 

[Kasun Bandara]

yes. also if you have different networks between client and DHCP server, you need to use helper address to route DHCP traffic to DHCP server.

https://techexpert.tips/cisco-switch/dhcp-relay-on-cisco-switch/

[Tom101]

Hi Kasun, thank you for your response. I have given each VLAN an ip helper address on the L3Switch01 device. Is this what you meant? It is still having some problems routing the traffic which i can't figure out why. 

interface Vlan1
 ip address 203.20.10.1 255.255.255.0
!

interface Vlan20
 mac-address 00d0.bcb8.d101
 ip address 20.20.20.254 255.255.255.0
 ip helper-address 10.10.10.1
!

interface Vlan30
 mac-address 00d0.bcb8.d103
 ip address 30.30.30.254 255.255.255.0
 ip helper-address 10.10.10.1
!

[Kasun Bandara · Accepted solution]

change your DHCP server gateway to 10.10.10.3. because dhcp server sends ICMP to new dhcp leasing IP for check availability of new ip. your server GW is pointed to L2sw1 and that switch doesnt know where to route ICMP check packet. since L3 switch doing the routing part, your GW for DHCP server need to be L3 switch.

or change your L2 switch IP to 10.10.10.3 and L3sw ip to 10.10.10.254

[Tom101]

Thank you so much. That worked perfectly. Well explained too.