Juniper JUNOSE, Configuration Manual

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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 Name Reason Subcode
Maximum Number of Prefixes Reached The 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 Shutdown The BGP speaker is administratively
shutting down the session. 2
Peer Unconfigured The BGP speaker is removing the peer
configuration. 3
Administratively Reset The BGP speaker is administratively
resetting the session. 4
Connection Rejected The 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 Change The 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.
BGP Route
A BGP route consists of two parts, a prefix and a set of path attributes. It is not
uncommon to use the term path to refer to a BGP route, although that term technically
refers to one of the path attributes of that route.
Routing Information Base
BGP routes are stored in a BGP speaker’s routing information base (RIB), also known
as its routing table, which conceptually consists of the following three parts:
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Overview
JUNOSe 11.0.x BGP and MPLS Configuration Guide