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traceoptions (Spanning Tree)


Hierarchy Level


Sets protocol-level tracing options for for spanning-tree protocols MPLS, MVRP, STP, RSTP, MSTP, and VSTP.


The default STP protocol-level trace options are inherited from the global traceoptions statement. Traceoptions is disabled.


disable—(Optional) Disable the tracing operation. One use of this option is 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. We recommend that you place STP tracing output in the file /var/log/stp-log.

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 must also specify a maximum file size with the size option.

  • Range: 2 through 1000 files

  • Default: 1 trace file only

flag—Tracing operation to perform. To specify more than one tracing operation, include multiple flag statements. The following are the STP-specific tracing options:

  • all—Trace all operations.

  • all-failures—Trace all failure conditions.

  • bpdu—Trace BPDU reception and transmission.

  • bridge-detection-state-machine—Trace the bridge detection state machine.

  • error—Trace all failure conditions.

  • events—Trace events of the protocol state machine.

  • pdu—Trace PDUs that were received and sent.

  • port-information-state-machine—Trace the port information state machine.

  • port-migration-state-machine—Trace the port migration state machine.

  • port-receive-state-machine—Trace the port receive state machine.

  • port-role-transit-state-machine—Trace the port role transit state machine.

  • port-role-select-state-machine—Trace the port role selection state machine.

  • port-state-transit-state-machine—Trace the port state transit state machine.

  • port-transmit-state-machine—Trace the port transmit state machine.

  • ppmd—Trace the state and events for the ppmd process.

  • socket—Trace socket activity.

  • state-machine—Trace state machine information.

  • state-machine-variables—Trace when the state machine variables change.

  • timers—Trace protocol timers.

  • topology-change-state-machine—Trace the topology change state machine.

The following are the global tracing options:

  • all—All tracing operations.

  • config-internal—Trace configuration internals.

  • general—Trace general events.

  • normal—All normal events.

  • Default: If you do not specify this option, only unusual or abnormal operations are traced.

  • parse—Trace configuration parsing.

  • policy—Trace policy operations and actions.

  • regex-parse—Trace regular-expression parsing.

  • route—Trace routing table changes.

  • state—Trace state transitions.

  • task—Trace protocol task processing.

  • timer—Trace protocol task timer processing.

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

replace—(Optional) Replace an existing trace file if there is one.

  • Default: If you do not include this option, tracing output is appended to an existing trace file.

size size—(Optional) Maximum size of each trace file, in kilobytes (KB) or megabytes (MB). 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 must also 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: 1 MB

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

Required Privilege Level

routing—To view this statement in the configuration.

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

Release Information

Statement introduced in Junos OS Release 8.4.

Statement updated in Junos OS Release 9.4 for EX Series switches to add VSTP support.

Support for logical systems added in Junos OS Release 9.6.