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Hierarchy Level


Configure trace options for Bidirectional Forwarding Protocol (BFD) traffic. Configure seamless BFD (S-BFD) over non-colored static segment-routing LSPs with first-hop label resolution and use S-BFD as a fast mechanism to detect path failures and to trigger global convergence.


If you do not include this statement, no BFD tracing operations are performed.


disable—(Optional) Disable the BFD tracing operation. You can use this option to disable a single operation when you have defined a broad group of tracing operations, such as all.

file filename—Name of the file to receive the output of the tracing operation. Enclose the name in quotation marks. All files are placed in the /var/log directory . We recommend that you place global routing protocol tracing output in the routing-log file.

files number—(Optional) Maximum number of trace files. When a trace file named trace-file reaches its maximum size, it is renamed trace-file.0, then trace-file.1, and so on, until the maximum number of trace files is reached. Then the oldest trace file is overwritten.

If you specify a maximum number of files, you also must specify a maximum file size with the size option.

  • Range: 2 through 1000 files

  • Default: 2 files

flag flag—Tracing operation to perform. To specify more than one tracing operation, include multiple flag statements. These are the BFD protocol tracing options:

  • adjacency—Trace adjacency messages.

  • all—Trace all options for BFD.

  • error—Trace all errors.

  • event—Trace all events.

  • issu—Trace in-service software upgrade (ISSU) packet activity.

  • nsr-packet—Trace non-stop-routing (NSR) packet activity.

  • nsr-synchronization—Trace NSR synchronization events.

  • packet—Trace all packets.

  • pipe—Trace pipe messages.

  • pipe-detail—Trace pipe messages in detail.

  • ppm-packet—Trace packet activity by periodic packet management (PPM).

  • state—Trace state transitions.

  • timer—Trace timer processing.

match regular-expression—(Optional) Regular expression for lines to be logged.

no-world-readable—(Optional) Prevent any user from reading the log file.

size size—(Optional) Maximum size of each trace file, in kilobytes (KB), megabytes (MB), or gigabytes (GB). When a trace file named trace-file reaches this size, it is renamed trace-file.0. When the trace file again reaches its maximum size, trace-file.0 is renamed trace-file.1 and trace-file is renamed trace-file.0. This renaming scheme continues until the maximum number of trace files is reached. Then, the oldest trace file is overwritten.

If you specify a maximum file size, you also must specify a maximum number of trace files with the files option.

  • Syntax: xk to specify KB, xm to specify MB, or xg to specify GB

  • Range: 10 KB through the maximum file size supported on your system

  • Default: 128 KB

world-readable—(Optional) Allow any user to read the log file.

sbfd—Seamless BFD parameters. In S-BFD, each responder might have multiple discriminators. The discriminators might be advertised by IGP to other routers, or they might be statically configured on these routers.

local-discriminator value—Local discriminator for seamless BFD responder.

Range: 1 through 4294967295.

  • local-ip-address IP address—IPv4 source address.

  • minimum-receive-interval value—Minimum receive interval for seamless BFD responder.

    Range: 10 through 255000 milliseconds.

local-discriminator-ip IP address—Local discriminator IP address for sBFD responder.

pool value—List of seamless BFD endpoints.

Required Privilege Level

routing and trace—To view this statement in the configuration.

routing-control and trace–control—To add this statement to the configuration.

Release Information

Statement introduced before Junos OS Release 7.4.