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.