the BFD protocol session goes down, BGP immediately brings down the BGP session
and takes all associated actions.
Whenever a BGP session leaves the established state, BGP requests BFD to stop the
BFD protocol session. BGP also requests BFD to bring the BFD protocol session down
and inform BGP if the local interface goes down.
To enable a BGP session to come up even if the remote peer does not support BFD
or has not been configured to use BFD, the following behavior applies:
■
The BGP session can come up when the BFD protocol session is not yet up.
■
The BGP session can stay up even when the BFD protocol session never comes
up.
You can specify a desired rate for receiving BFD packets from the peer, transmitting
them to the peer, or both, by setting a desired time interval between the packets.
The actual timer values can be different as a result of other applications requesting
BFD protocol sessions on the same interface with different timer values, as a result
of timer value negotiation between the local and remote BFD speakers, or both.
In the following example, the router is configured to send BFD packets to peer
10.25.43.1 with a minimum interval of 450 milliseconds between the packets, and
to accept BFD packets from the peer only with the same minimum interval:
host1(config)#
router bgp 100
host1(config-router)#
neighbor 10.25.43.1 bfd-liveness-detection minimum-interval
450
neighbor bfd-liveness-detection
■
Use to enable BGP to detect whether a neighbor is unreachable by means of a
BFD protocol session to the neighbor.
■
The peers in a BGP adjacency use the configured values to negotiate the actual
transmit intervals for BFD packets.
■
You can use the
minimum-transmit-interval
keyword to specify the interval
at which the local peer proposes to transmit BFD control packets to the
remote peer. The default value is 300 milliseconds.
■
You can use the
minimum-receive-interval
keyword to specify the minimum
interval at which the local peer must receive BFD control packets from the
remote peer. The default value is 300 milliseconds.
■
You can use the
minimum-interval
keyword to specify the same value for
both of those intervals. Configuring a minimum interval has the same effect
as configuring the minimum receive interval and the minimum transmit
interval to the same value. The default value is 300 milliseconds.
■
You can use the
multiplier
keyword to specify the detection multiplier value.
The calculated BFD liveness detection interval can be different on each peer.
The multiplier value is roughly equivalent to the number of packets that can be
missed before the BFD session is declared to be down. The default value is 3.
■
For details on liveness detection negotiation, see
JUNOSe IP Services Configuration
Guide
.
142
■
Detecting Peer Reachability with BFD
JUNOSe 11.0.x BGP and MPLS Configuration Guide
Содержание JUNOSE
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Страница 37: ...Part 1 Border Gateway Protocol Configuring BGP Routing on page 3 Border Gateway Protocol 1...
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Страница 234: ...198 Monitoring BGP JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 236: ...200 Multiprotocol Layer Switching JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 298: ...262 Point to Multipoint LSPs Configuration JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 346: ...310 Example Traffic Class Configuration for Differentiated Services JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 535: ...There is no no version See undebug ip mbgp Monitoring BGP MPLS VPNs 499 Chapter 5 Configuring BGP MPLS Applications...
Страница 536: ...500 Monitoring BGP MPLS VPNs JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 538: ...502 Layer 2 Services Over MPLS JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 592: ...556 Multiple ATM Virtual Circuits over a Single Pseudowire Example JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 604: ...568 Virtual Private LAN Service JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 618: ...582 VPLS References JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 642: ...606 VPLS Configuration Example with LDP Signaling JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 674: ...638 Virtual Private Wire Service JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 718: ...682 Monitoring MPLS Forwarding Table for VPWS JUNOSe 11 0 x BGP and MPLS Configuration Guide...
Страница 719: ...Part 6 Index Index on page 685 Index 683...
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