Juniper JUNOSE 11.2.X BGP AND MPLS User Manual

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Keepalive messages—BGP speakers periodically exchange keepalive messages to
determine whether the underlying TCP connection is still up.
•
Notification messages—If a BGP speaker wishes to terminate a BGP session (either
because it has been configured to do so or because it has detected some error
condition), it will send a notification message to its peer specifying the reason for
terminating the BGP session.
If the session is being terminated for a nonfatal error, the notification messages includes
the error code cease. Subcodes sent in the notification message can inform network
operators about peering problems and help them better understand network events.
Table 4 on page 8 lists the subcodes defined for BGP notification messages bearing
the cease code.
Table 4: Cease Notification Message Subcodes
Symbolic NameReasonSubcode
Maximum Number of Prefixes ReachedThe number of address prefixes received
from the peer has exceeded the upper
bound configured with the neighbor
maximum-prefix command. The
notification message can include address
family and upper bound information in
the data field.
1
Administratively ShutdownThe BGP speaker is administratively
shutting down the session.
2
Peer UnconfiguredThe BGP speaker is removing the peer
configuration.
3
Administratively ResetThe BGP speaker is administratively
resetting the session.
4
Connection RejectedThe BGP speaker is rejecting the
connection (for example, because the
peer is not configured locally on the
speaker) after accepting a transport
protocol connection.
5
Other Configuration ChangeThe BGP speaker is administratively
resetting the session for some other
configuration.
6
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Route-refresh messages—BGP speakers can send route-refresh messages to peers
that advertise the route-refresh capability. The messages contain a request for the
peer to resend its routes to the router. This feature enables the BGP speaker to apply
modified or new policies to the routes when it receives them again.
Copyright © 2010, Juniper Networks, Inc.8
JunosE 11.2.x BGP and MPLS Configuration Guide

Juniper JUNOSE 11.2.X BGP AND MPLS Specifications

General

Brand	Juniper
Model	JUNOSE 11.2.X BGP AND MPLS
Category	Software
Language	English