In this article I would like to cover how to configure SNMPv3 for Cisco Identity Services Engine (ISE). In a few deployments I’ve done, I’ve come across the need to configure ISE to send SNMPv3 traps to a Network Management System (NMS). SNMPv3 is perfect for ensuring the authentication and encryption of SNMP traffic, something that can’t be done with inferior SNMP versions. Now, one would assume that we could just go ahead and configure ISE for SNMP via the GUI however, unfortunately that’s not the case. To actually configure ISE to send traps to an NMS system we need to configure the settings via the CLI. The demonstration in the article is performed using a standalone ISE. This demonstration also assumes that you have connectivity between your NMS platform and ISE. To see a live demonstration with testing, refer to the video that accompanies this article. Configuration Steps Enable SNMP So that we can configure the required SNMPv3 settings for ISE, SNMP needs to be enabled. iselab/a...
In this article we are going to take a look at how to capture Extensible Authentication Protocol Over LAN (EAPOL) and Remote Authentication Dial-In User Service (RADIUS) packets using Wireshark. This article can be useful for troubleshooting 802.1x within your environment and can also be used for learning purposes. The following topology has been used to gather the required output for this article. Note: This article will only cover the switch configurations that are required to gather EAPOL and RADIUS configuration. Overview of the Topology The supplicant is configured to perform 802.1x using EAP-TLS as the authentication method The user certificate on the supplicant will be used for authentication The supplicant has Wireshark installed Cisco ISE is used for authentication and authorisation The supplicant is assigned to VLAN 10 upon authentication and all other endpoint ports are assigned to VLAN 99 Sniffer device is running Wireshark in order to capture RADIUS flows via SPAN 802.1x ...
Throughout my time working with Cisco ISE, I’ve come across a few different errors when configuring ISE to perform Certificate Revocation Lists (CRL) lookups using Microsoft’s Public Key Infrastructure (PKI). In this article I would like to show you how we can avoid CRL download issues that could ultimately stop an endpoint from authenticating onto a network when configured for Network Authentication Control (NAC). CRL checking is useful for checking of expired certificates and when an environment has Cisco Identity Services Engine deployed for secure network access, this can be useful for ensuring revoked digital certificates are not reused when they’ve been revoked. CRL lookups can be costly to your network because of the lookups that are performed and Online Certificate Status Protocol (OCSP) can be used as a more efficient way to check revoked certificates. However for the purpose of this article we will focus only on Certificate Revocation Lists. In this article I will demonstrate...
If you're familiar with Cisco ISE deployments, then no doubt you've encountered a time where an Administrator password has expired and needs to be reset. This can happen for a number of reasons however the most common would be because of the admin password expiry setting that hasn't been disabled in ISE. When setting up a new Cisco ISE deployment, you will set the admin password. It is important to note that the CLI and GUI admin password can be different. Although you can reset the admin GUI password via the CLI when it has expired, if the CLI password expires or you forget it, you will be required to boot from the .ISO in order to reset the password. Booting from the .ISO can be a pain if ISE nodes are in a production environment and you may find that you need a change window to do this. Whatever the case may be, this article focuses on how to reset the admin passwords while ISE is in production. These steps were taken when I encountered a similar issue with a distributed...
In this video, we take a look at what is required to join a Cisco Lightweight Access Point (LWAP) to a Cisco Virtual Wireless Controller (vWLC). Devices in this video include: Cisco vWLC Cisco LWAP c1600 series Windows Server 2012 R2 Updated Notes: 28/09/2019 Having worked with AP's and WLC's some more, I wanted to share some more notes from things observed in my lab. The output below is generated from a C1600 series AP that I have in my lab. The syslog output is generated when the AP attempts to join the WLC. While looking into this, I found a few workarounds and potential bugs associated with this. *Sep 28 19:38:19.066: AP has SHA2 MIC certificate - Using SHA2 MIC certificate for DTLS. *Sep 28 19:38:18.000: %CAPWAP-5-DTLSREQSEND: DTLS connection request sent peer_ip: 192.168.101.2 peer_port: 5246 *Sep 28 19:38:23.999: DTLS_CLIENT_ERROR: ../capwap/base_capwap/dtls/base_capwap_dtls_handshake.c:929 Unexpected message received while expecting HelloVerifyRe...