http://www.rfc-editor.org/rfc/rfc6608.txt
RFC 6608: Subcodes for BGP Finite State Machine Error, J. Dong, M. Chen, A. Suryanarayana2012-05-01T23:00:00-00:00This document defines several subcodes for the BGP Finite State Machine (FSM) Error that could provide more information to help network operators in diagnosing BGP FSM issues and correlating network events. This document updates RFC 4271. [STANDARDS-TRACK]