ElderUsr's Blog

This document will outline some basic troubleshooting steps and issues that I have found out over the years about 4500 Series Switches, specifically Supervisors 4-5, but it is mainly relevant for all models. Additional Reading: BRKCRS-3142 - Troubleshooting Cisco 4500 Series Switches Scope The scope of items that are being impacted, such as in an test environment 1 Core Switch, to two Distribution to then two Access switches per Distribution switch always keep in mind of where the issue is occurring and what is being impacted. Some of the situations below I will mention if its common for all devices to be impacted, or only certain ones. Please note that this is not necessarily Cisco's best practice, but it is how I have it setup when testing/experiences was issued. High CPU Process Troubleshooting Typical Causes: a) Multicast Traffic (IGMP) b) Spanning-Tree Traffic c) Consecutive Port Changes (Port-Flapping) Enabling CPU "Output" to a Wireshark Session ...

Below is a set of Random Cisco & FortinetCommands that are common to be used and what it does: #[Cisco] Enabling Mac Filtering on Ports & auto-recovery for the port. switchport port-security switchport port-security mac-address switchport port-security maximum 1 errdisable recovery cause psecure-violation #[Cisco] Checking Hardware/CPU show module more crashinfo:data show processes cpu [history | sorted] show processes memory [sorted]   #[Fortinet] Showing information about Link-Monitoring in redundant links diag sys link-monitor status    

Implementing 802.1X Using Windows Server 2012R2 & Cisco 4500 Series Switches Overview: This document is to outline how the configuration between Windows Server 2012 R2’s NPS Services and Cisco 4500 Series switches has been implemented. High Level Diagram:   Requirements: Windows Server 2012 R2 with NPS Server installed Windows Server 2012 R2 with CA Services Windows AD Environment Cisco 4500 Series Switches Windows 7-10 Clients to connect NPS Configuration: 1. This assumes the above requirement that the NPS Service has already been installed on Windows Server 2012 R2 2. Disable all existing Policies under Connection Request Policies and Network Policies as you will be making your own, except one that states “Catch All” with the below parameters: 3. You will then need to add in a new Radius Client to have Policies built around. Friendly Name will be used going forward for the Policies for referencing the document. 4. Once completed...

This will be the first post of a bunch outlining a bunch of configurations and setups that I have performed in the past few years since updating this blog. TACACS Configuration: aaa authentication login default group tacacs+ local aaa authentication enable default group tacacs+ enable aaa authorization config-commands aaa authorization commands 0 default group tacacs+ local aaa authorization commands 1 default group tacacs+ local aaa authorization commands 7 default group tacacs+ local aaa authorization commands 15 default group tacacs+ local aaa accounting commands 0 default start-stop group tacacs+ aaa accounting commands 1 default start-stop group tacacs+ aaa accounting commands 7 default start-stop group tacacs+ aaa accounting commands 15 default start-stop group tacacs+ aaa accounting network 0 start-stop group tacacs+ aaa accounting network 15 start-stop group tacacs+ aaa accounting connection 0 start-stop group tacacs+ aaa accounting connection 15 start-stop group tacacs+ t...