BGP Troubleshooting with Cisco Routers – Determining Upstream ISP Fault

Sporadic BGP issues can be difficult to troubleshoot sometimes, especially when the routing issues you face are further upstream (ISP controlled) and out of your control. Finding the root cause can be a problem. Part of the reason this is difficult is because Cisco Routers only log BGP neighbor state changes by default, and not “route update” or “route withdrawal messages”. Continue reading “BGP Troubleshooting with Cisco Routers – Determining Upstream ISP Fault”