In this video, we take a look at how EEM scripts can be utilized alongside Low Impact mode to enable ports to fail open.
Below are EEM Scripts that can be reused and modified for your environment.
Note: For single RADIUS Servers use the “%RADIUS-4-RADIUS_DEAD” syslog pattern and for a group of RADIUS servers use the “%RADIUS-3- ALLDEADSERVER” syslog pattern.
If your devices utilize command authorization then you need to ensure that the script can still run in the event of a failure. Enter the following command at the end of each applet to ensure command authorization is bypassed.
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 ...
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...
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...
In this quick tip Cisco ISE article I would like to point out how ISE administrators can displays usernames for failed authentications. The following has been tested on ISE 2.4 but is relevant for older ISE versions. When a user/machine fails authentication ISE will mask the identity automatically. This can be seen in the RADIUS Live Logs and looks like the screenshot (1) shown below. Although you can click on the details of each live log, sometimes it’s good to know what the identity is to troubleshoot further. The good news is that with ISE, we can unmask the identity, however, the bad news for some is that you can only keep identities unmasked for a limited time, depending on ISE version. As of up to ISE 2.4 patch 3 you cannot keep identities unmasked permanently, in fact, the maximum time in which you can keep identities unmasked for is 30 minutes before ISE masks them again. As mentioned, this is not convenient and was in fact raised as a bug (CSCvh91118). I believe ISE releases ...
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...
