You are assessing BGP between two Juniper routers, and the BGP session remains in the Idle state.
What could cause this behavior?
An incorrect peer IP address prevents the router from establishing the TCP connection to the intended BGP neighbor, so the BGP finite-state machine cannot progress to an established session. Juniper documents that inability to reach a peer’s IP address indicates a TCP transport connection problem, and that BGP returns to Idle when errors occur. Troubleshooting BGP Sessions | Junos OS | Juniper Networks
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