These links were recommended to me for a quick read (Not so quick read):
- Troubleshooting Frame Relay Connections:
- Troubleshooting Serial Line Problems:
- Frame Relay comprehensive Guide to Configuring and Troubleshooting Frame Relay
- T1/E1 & T3/E3 Blue and Yellow T1 Alarm Troubleshooting
- Cisco Port Adapters Troubleshooting Ethernet Collisions
- Cisco 7500 Series Routers troubleshooting High CPU Utilization in IP Input
- Cisco 7500 Series Routers troubleshooting High CPU Utilization due to Processes
- Cisco 90 Series Customer Premises Equipment Troubleshooting Router Crashes