Cisco ISE Part 10: Profiling and posture

This is a Cisco ISE blog post series with some how-to’s for configuring the ISE deployment, This blog post series exists of 10 parts.

The blogpost Agenda:

Part 1: introduction
Part 2: installation
Part 3: Active Directory
Part 4: High Availability
Part 5: Configuring wired network devices
Part 6: Policy enforcement and MAB
Part 7: Configuring wireless network devices
Part 8: Inline posture and VPN
Part 9: Guest and web authentication
Part 10: Profiling and posture

This week, the last post in the Cisco ISE blog post series: Profiling and posture. For both features is the Cisco ISE advanced license required.

Profiler is a functionality for discovering, locating and determing the capabilities of the attached endpoints. It will detect the network type and will authorize it.

A sensor in the network captures network packets by quering the NADs, it forwards the attributes to the analyzer. The analyzer checks the attributes using policies and identity groups. The results is stored in the ISE database with the corresponding device profile. The MAC address of the device will be linked to a existing endpoint identity group.

There are 9 availabled probes:

  • Netflow
  • DHCP
  • DHCP SPAN
  • HTTP
  • RADIUS
  • NMAP
  • DNS
  • SNMPQUERY
  • SNMPTRAP

Profiling uses CoA (change of authorization). There are 3 options:

  • No CoA: CoA is disabled
  • Port bounce: use this only of there is a single session on a switchport
  • Reauth: enforce reauthentication of a currently authenticated endpoint when it’s profiled

ISE creates three identity groups by default and two identity groups that are specific for Cisco IP phones. Creation of extra groups is optional.

An endpoint profiling policy contains a simple condition or a set of conditions (compound).

Configuring

Probe configuration

First, make sure the ISE appliance can SNMP to the switches (SNMPv2 or 3) with a read only community string. Also, configure a snmp trap destination to Cisco ISE policy node.

Switch(config)# snmp-server host 172.20.12.5 version 3 priv ISE
Switch(config)# snmp-server enable traps snmp linkdown linkup
Switch(config)# snmp-server enable traps mac-notification change move

On all interfaces:
Switch(config-if)# snmp trap mac-notification change added

For DHCP probing, configure an additional IP helper on the SVI to the policy node:

Switch(config-if)# ip helper-address 172.20.12.5

Cisco ISE configuration

Click Administration – System – Settings, click Profiling and configure the CoA.

profile5

Click Administration – System – Deployment – Deployment. Choose the node and click edit. Select the Profiling configuration tab. Enable and configure the probes as needed.

profile1

Next, click: Administration – Network resources – Network devices and edit your switch. Scroll down and check/edit the SNMP settings.

profile2

To create a new policy: Click Policy – Profiling, choose Profiling policies and click Create.
Enter a name, a minimum certaincy factor and a exception action. Apply the needed rules with the certaincy factors.

profile6

To check the discovered endpoints, click Administration – Identity management – identities – endpoints.

profile4

Monitor the authentication by clicking Monitor – Authentications.

Appendix

If you want to use IOS probing with a switch on IOS 15.0 or newer, use the following configuration:

Switch(config)#device-sen
Switch(config)#device-sensor filter-list dhcp list dhcp-list
Switch(config-sensor-dhcplist)#option name host-name
Switch(config-sensor-dhcplist)#option name all-subnets-local
Switch(config-sensor-dhcplist)#option name trailer-enca
Switch(config-sensor-dhcplist)#option name trailer-encapsulation 
Switch(config-sensor-dhcplist)#!
Switch(config-sensor-dhcplist)#device-sen
Switch(config-sensor-dhcplist)#device-senso
Switch(config-sensor-dhcplist)#device-sensor
Switch(config-sensor-dhcplist)#device-sensor filter
Switch(config-sensor-dhcplist)#device-sensor filter-li
Switch(config-sensor-dhcplist)#device-sensor filter-list cdp list CDP_LIST
Switch(config-sensor-cdplist)#tlv name device-name
Switch(config-sensor-cdplist)#tlv name address-type
Switch(config-sensor-cdplist)#tlv name platform-type
Switch(config-sensor-cdplist)#tlv name power-type
Switch(config-sensor-cdplist)#tlv name external-port-id-type
Switch(config-sensor-cdplist)#device-sensor filter-sepc cdp include list CDP_LIST
Switch(config)#device-sensor filter-spec cdp include list CDP_LIST
Switch(config)#device-sen
Switch(config)#device-sensor accounting
Switch(config)#device-
Switch(config)#device-sensor not-   
Switch(config)#device-sensor not 
Switch(config)#device-sensor notify all
Switch(config)#device-sensor notify all-changes

Posture

To check inside a host for available antivirus, firewall, registry keys etc, posture is being used. A NAC agent is needed for this.

There are 3 modes:

  • Audit (audit only)
  • Optional (client can ignore the result)
  • Mandatory

The most common conditions:

  • Windows update
  • Virus application
  • Virus definition
  • Windows screensaver password
  • Registry entry

The NAP client is using the SWISS protocol (UDP/8905). Make sure the client can connect to the policy node on UDP/8905. A client can download the NAC client (it’s read-only software). There are againts for Windows, MAC OS-X and a web agent.

The provisioning flow:

  • Client provisioning
  • Posture subscription and policy
  • Authorization policy

Make sure the ISE appliance is up to date with the latest posture files. You can download those from the Cisco website with a CCO account. These updates are a set of predefined checks, rules and antivirus support charts. These updates can be downloaded automatically. Check this by clicking Administration – System – Settings – Posture – updates

This was a 10 series blog post about Cisco ISE. Hope you’ll liked it!