DHCP relay for L2 switches

RussMcIntire — Thu, 19 Mar 2020 01:28:39 GMT

I am working on a network segmentation project for our organization. We currently run Cisco switches and all devices reside on the default VLAN, VLAN 1. All routing is currently done on our PA-850. On the PA-850, I have configured the new VLAN's as sub-interfaces and all switches for layer 2. If I put a PC on any VLAN and set a static IP address, I can ping all gateways and any other IP address on any other VLAN. So far so good.

The issue I have is DHCP. I can get DHCP addresses for VLAN 1 (the Cisco default VLAN) from our Windows 2019 servers, but no other VLAN even though DHCP helpers are configured on the switches. On the switches, VLAN 1 is un-tagged but all other VLAN's are tagged.

Is it possible to set up a DHCP relay on the PA-850 so the added VLAN's can pull an address from the windows DHCP server? If so, can anyone give me some guidance on how to proceed?

Any help would be greatly appreciated.

Re: DHCP relay for L2 switches

BPry — Thu, 19 Mar 2020 01:50:27 GMT

@RussMcIntire,

As long as you have configured the vlan interfaces as layer-3, follow the following KB to setup the DHCP relay on the firewall.

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClFXCA0

Re: DHCP relay for L2 switches

RussMcIntire — Thu, 19 Mar 2020 14:57:39 GMT

That worked! 🙂 All clients tested are pulling the correct IP addresses!

Thanks for the quick response

topic DHCP relay for L2 switches in General Topics

DHCP relay for L2 switches

Re: DHCP relay for L2 switches

Re: DHCP relay for L2 switches