Fix Cisco ISE Messaging Service

Cisco Identity Services Engine 2.6 introduced the concept of the ISE Messaging Service as an encrypted, lightweight protocol to replace syslog communication between the ISE nodes for logging purposes.  The ISE Messaging Services runs over TCP/8671.  In 2.6 Patch 2 and later, the Cisco ISE Messaging Service is enabled by default.  

The overall implementation of the ISE Messaging Service has been buggy (but has gotten much better in recent versions) in both new ISE builds and upgrades.  One solution is simply to disable the ISE Messaging Service within Administration > System > Logging.  But then the ISE logging traffic isn't encrypted and the legacy syslog delivery method is not as efficient as the ISE Messaging Service so we will focus the rest of this article on how to identity and fix the ISE Messaging Service.

Problem Identification

Usually problems with the ISE Messaging Service involve a blank Live Logs page.  You know authentication is working as you have devices/users successfully authenticated via RADIUS, Guest, or TACACS+.  The best way to confirm this is to look for the Queue Link Alarms in the ISE dashboard Alarm section.  Specifically the details around this will mention a certificate issue, most commonly Unknown CA.

Resolution

  1. Re-generate ISE Root CA Chain within Administration > System > Certificates > Certificate Management > Certificate Signing Request (CSR). Click Generate Certificate Request (CSR) and choose ISE Root CA in the drop-down list.  Finally, click Replace ISE root CA Certificate Chain.
  2. Re-generate the ISE Messaging Service Certificate.  Administration > System > Certificates > Certificate Management > Certificate Signing Request (CSR). Click Generate Certificate Request (CSR) and choose ISE Messaging Service in the drop-down list.  Finally click Generate CSR.
Live Logs should begin to appear in the Live Logs section and you should see no additional Queue Link Alarms in the Dashboard Alarms.  Note that the regeneration of the Root CA or ISE Messaging service does not cause a service restart on any of the ISE nodes.  

-A

Comments

Post a Comment

Popular posts from this blog

ClearPass MPSK per Device Type with Profiling

Image
Multiple Pre-Shared Key or MPSK helps solve for IOT or other endpoint device types that are not 802.1X capable.  The Aruba ClearPass default implementation of MPSK (the configuration created by the wizard) requires manually registering, enrolling, and managing individual PSK keys per endpoint using the ClearPass Guest dashboard.  While the most secure approach, excluding any sort of API based automation, this can obviously be a nightmare to manage and support due to the sheer number of PSKs.  This approach instead delivers a unique PSK per device type (printer, thermostat, etc.) so that each flavor of endpoint would have its own PSK.  If one PSK was compromised, then only those endpoints would need to be manually re-configured.  PSK rotation would also be limited to only those specific device types allowing rotation to take place slowly over several weeks rather than all devices at the same time on the SSID with a traditional single PSK; lessoning the burden on IT staff and minimizing
Read more

Cisco Designated VIP 2023

I'm happy to announce that I have been recognized as a Cisco Community Designated VIP for 2023 for my assistance in the Cisco Secure Network Access Control community focusing on Identity Services Engine.  Be sure to check out all of the Cisco Community Designated VIPs .
Read more