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#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)
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