topic Re: DHCP relay issue in General Topics

DHCP relay issue

stef — Thu, 25 Nov 2021 10:16:42 GMT

Hello all,

I have an issue with the DHCP.

I have DHCP relay configured on the device (PA820), remote windows server, connectivity and policy permitting DHCP traffic.

The problem is that the traffic is sill dropped by the FW, classified as not applicable.

Can someone advice ? Thank you in advance!

Re: DHCP relay issue

johnwalshaw — Thu, 25 Nov 2021 22:33:59 GMT

Keep in mind that DHCP is a conversation that happens before there is an IP address assigned, so the concept of a session might be different. I have not tested this on Palo myself. Maybe add both zones on the source and dest. My experience was Cisco ISR ACL and that was quite interesting.

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

Re: DHCP relay issue

BPry — Thu, 25 Nov 2021 23:44:29 GMT

@stef,

The traffic on the firewall will simply look like the client is communicating directly to the DHCP host that you have setup as the relay target, so make sure that you are actually allowing the traffic properly in your rulebase. Use the 'test security-policy-match' command to verify that you actually have the security rulebase entry built out properly.