bfd-liveness-detection (Protocols IS-IS)
Syntax
bfd-liveness-detection {
authentication {
algorithm algorithm-name;
key-chain key-chain-name;
loose-check;
}
detection-time {
threshold milliseconds;
}
minimum-interval milliseconds;
minimum-receive-interval milliseconds;
multiplier number;
no-adaptation;
transmit-interval {
minimum-interval milliseconds;
threshold milliseconds;
}
version (1 | automatic);
}
Hierarchy Level
[edit logical-systems logical-system-name protocols isis interface interface-name], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols isis interface interface-name], [edit protocols isis interface interface-name], [edit protocols isis interface interface-name family inet|inet6], [edit routing-instances routing-instance-name protocols isis interface interface-name]
Description
Configure bidirectional failure detection timers and authentication.
Starting with Junos OS Release 16.1, you can configure
IS-IS BFD sessions for the IPv6 address family. Therefore, this configuration
statement is also available under the [edit protocols isis interface interface-name family inet|inet6] hierarchy level.
The BFD failure detection timers are adaptive and can be adjusted to be faster or slower. For example, the timers can adapt to a higher value if the adjacency fails, or a neighbor can negotiate a higher value for a timer than the configured value. The timers adapt to a higher value when a BFD session flap occurs more than three times in a span of 15 seconds. A back-off algorithm increases the receive (RX) interval by two if the local BFD instance is the reason for the session flap. The transmission (TX) interval is increased by two if the remote BFD instance is the reason for the session flap.
You can use the clear bfd adaptation command to return
BFD interval timers to their configured values. The clear bfd
adaptation command does not affect traffic flow on the routing
device.
Options
authentication algorithm algorithm-name —Configure the algorithm used to authenticate the specified
BFD session: simple-password, keyed-md5, keyed-sha-1, meticulous-keyed-md5, meticulous-keyed-sha-1.
authentication key-chain key-chain-name—Associate a security key with the specified BFD session
using the name of the security keychain. The name you specify must
match one of the keychains configured in the authentication-key-chains
key-chain statement at the [edit security] hierarchy
level.
authentication loose-check—(Optional) Configure
loose authentication checking on the BFD session. Use only for transitional
periods when authentication might not be configured at both ends of
the BFD session.
detection-time threshold milliseconds—Configure a threshold for the adaptation of the BFD
session detection time. When the detection time adapts to a value
equal to or greater than the threshold, a single trap and a single
system log message are sent.
minimum-interval milliseconds—Configure the minimum interval after which the local routing
device transmits a hello packet and then expects to receive a reply
from the neighbor with which it has established a BFD session. Optionally,
instead of using this statement, you can specify the minimum transmit
and receive intervals separately using the transmit-interval
minimum-interval and minimum-receive-interval statements.
Range: 1 through 255,000
minimum-receive-interval milliseconds—Configure the minimum interval after which the local
routing device expects to receive a reply from a neighbor with which
it has established a BFD session. Optionally, instead of using this
statement, you can configure the minimum receive interval using the minimum-interval statement.
Range: 1 through 255,000
multiplier number—Configure
the number of hello packets not received by a neighbor that causes
the originating interface to be declared down.
Range: 1 through 255
Default: 3
no-adaptation—Specify that BFD sessions not
adapt to changing network conditions. We recommend that you not disable
BFD adaptation unless it is preferable not to have BFD adaptation
enabled in your network.
transmit-interval threshold milliseconds—Configure the threshold for the adaptation of the BFD
session transmit interval. When the transmit interval adapts to a
value greater than the threshold, a single trap and a single system
message are sent. The interval threshold must be greater than the
minimum transmit interval.
Range: 0 through 4,294,967,295 (232 – 1)
transmit-interval minimum-interval milliseconds—Configure a minimum interval after which the local routing
device transmits hello packets to a neighbor. Optionally, instead
of using this statement, you can configure the minimum transmit interval
using the minimum-interval statement.
Range: 1 through 255,000
version—Configure the BFD version to detect: 1 (BFD version 1) or automatic (autodetect
the BFD version)
Default:
automatic
The remaining statements are explained separately. See CLI Explorer.
Required Privilege Level
routing—To view this statement in the configuration.
routing-control—To add this statement to the configuration.
Release Information
Statement introduced before Junos OS Release 7.4.
detection-time threshold and transmit-interval
threshold options added in Junos OS Release 8.2.
Support for logical systems introduced in Junos OS Release 8.3.
no-adaptation statement introduced in Junos OS Release 9.0.
authentication algorithm, authentication key-chain, and authentication loose-check options introduced in
Junos OS Release 9.6.