![Ticket#12: High Packet Loss on WAN Link – Diagnosing QoS Misconfigurations [CCNP Enterprise]](https://networkjourney.com/wp-content/uploads/2025/07/Ticket12_High-Packet-Loss-on-WAN-Link-–-Diagnosing-QoS-Misconfigurations_networkjourney.png)
Problem Summary A branch office reported high packet loss and poor application performance over the WAN. The issue impacted VoIP calls, Citrix sessions, and file transfers, despite the link being stable. Symptoms Observed Example CLI Output: Root Cause Analysis On investigation, engineers found: Root Cause: […]
![Ticket#11: BGP Neighbor Flap – Hold Timer Expiry Due to MTU Mismatch [CCNP Enterprise]](https://networkjourney.com/wp-content/uploads/2025/07/Ticket11_BGP-Neighbor-Flap-–-Hold-Timer-Expiry-Due-to-MTU-Mismatch_networkjourney-1.png)
Problem Summary An enterprise experienced intermittent BGP neighbor flaps between core and WAN routers. The problem began after a WAN upgrade to a new service provider with slightly different interface MTU defaults. Symptoms Observed Root Cause Analysis After deeper analysis using packet captures and interface […]
![Ticket#25: Server Reachable via Ping but Not SSH – TCP MSS Clamp Missing on Firewall [CCNP Enterprise]](https://networkjourney.com/wp-content/uploads/2025/07/Ticket25_Server-Reachable-via-Ping-but-Not-SSH-–-TCP-MSS-Clamp-Missing-on-Firewall_networkjourney.png)
Problem Summary A remote branch server (e.g., 10.1.20.10) was reachable via ping, but users could not SSH or access HTTPS applications hosted on it. The server was behind a firewall that performed NAT and IPSec VPN termination. Symptoms Observed Root Cause Analysis On closer inspection, […]
