topic Can you use DHCP reservation information to map USER-ID? in General Topics

Can you use DHCP reservation information to map USER-ID?

thartman — Tue, 26 Feb 2019 22:07:18 GMT

Weird question....but have to ask.

Small Office network

No AD

Use PA220 as a DHCP Server for users (even mobile devices).

DHCP Reservation Table has all the information that I think USER-ID could use.....is there a way to make this happen?

thought about trying to forward a log file out of Management Interface to the Trusted interface.....but just spitballing here.

Bottom line - trying to come up with a way that I don't have to make users authenticate (so to speak).

Like I said....weird question 🙂

thanx,

tlh

OtakarKlier — Tue, 26 Feb 2019 23:02:40 GMT

Hello,

Check out the following:

I'm sure there is a location where all users must authenticate to? If not then Captive Portal and /or Global Protect might be the way to go.

Just some thoughts.

Chacko42 — Wed, 27 Feb 2019 08:25:29 GMT

@thartman I don't think that this will work.

The DHCP DORA process has no user information involved - so how should the firewall map that IP to a user?

I would recommend to use internal globalprotect for UserID - that's the best reliable source for it - in the meantime, youcould use WMI probing

Ricky_Wang — Fri, 05 Feb 2021 04:17:12 GMT

If you use PA as DHCP server, you can feed PA DHCP logs back to itself, use hostname or MAC address as username.

Some devices report their hostname while getting IP from DHCP server, some don't. in this case, you have to use MAC address as username.

1. Enable USER-ID syslog listener UDP on management interface.

2. Configure PA to send DHCP lease-start logs to its management interface.

3. Configure Palo Alto Networks User-ID Agent Setup, in the Syslog filters:

Event Regex: DHCP\ lease\ started

Username Regex: hostname\ ([a-zA-Z0-9\\\._-]+)

Address Regex: ip\ ([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})\s

4. Configure Server Monitoring, to monitor itself management interface, apply above syslog filter.

Tested on my PA-VM 10.0.4. My mobile phone reports its hostname as android-xxxxxx

Ricky_Wang — Fri, 05 Feb 2021 04:24:56 GMT

OK. It seems someone already tested on old PAN-OS version as well: