Category Archives: IT-security

Using DHCP on PAN device as User-ID, based on device-name

 

If you’re using DHCP on a PAN device, and want to get a simple way to identify users machines / phone based on device names, you can do so easylie with syslog.

This setup will convert this logline from DHCP:

DHCP lease started ip 192.168.18.140 --> mac 34:02:86:XX:XX:XX - hostname PCNO00198, interface ethernet1/2

To This:

This works from 8.0.0 and up.

My setup:

Ethernet1/1 -> x.x.x.x    Untrust

Ethernet1/2 -> 192.168.18.1 INSIDE (DHCP Server)

Ethernet1/3 -> 10.198.100.1 Guest (DHCP Server)

All serviceroutes setup to use Ethernet1/2, 192.168.18.1 (since I don’t use the dedicated managementport. User Identification ACL has to be enabled for the Zone you want to monitor:

 

 

Step 1:

Under Device, Server Profiles, and Syslog. Create a syslog profile that forward logs UDP port 514 to your own devices interface ip.

Step 2: Then, go to Logsettings And create a new Log Setting-System, add (eventid eq lease-start) in filter, and the syslogprofile you created in step 1.

Step 3:

Create a syslogfilter. Go to User Identification, Usermapping, then Palo Alto Networks User-ID Agent Setup, then Syslogfilter, ADD, name it something like PA-DHCP, use Regex Identifiser,

Event Regex: DHCP\ lease\ started

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

Address Regex: ip ([A-F0-9a-f:.]+)

 

Step 4:

Under User Identification, and new Server Monitoring (User Identification Monitored Server), Enabled, Type Syslog Sender, and ip of sender (in my case 192.168.18.1, because of service routes), Connection Type: UDP , and the Syslog Filter you created in step 3

Step 5:

Allow the Interface to be used as User ID syslog listener-UDP. Go to Network, then Network Profiles, and Interface Mgmt. Create a interface Management profile, and allow User-ID Syslog Listener-UDP.

Attach this profile to the interface (in my case the Ethernet1/2  192.168.18.1)

And you’re good to go!

 

TIP: Be sure to have the right service routes configured if you’re not using management-interface.