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interface-traceoptions (DHCP)


Hierarchy Level


Configure extended DHCP tracing operations that can be enabled on a specific interface or group of interfaces.

Replaces deprecated interface-traceoptions statements at the [edit forwarding-options dhcp-relay] and [edit system services dhcp-local-server] hierarchy levels.

To enable the tracing operation on the specific interfaces, you use the interface interface-name trace statement.


file filename—Name of the file to receive the output of the tracing operation. Enclose the name within quotation marks. All files are placed in the directory /var/log.

files number—(Optional) Maximum number of trace files to create before overwriting the oldest one. If you specify a maximum number of files, you also must specify a maximum file size with the size option.

  • Range: 2 through 1000

  • Default: 3 files

flag flag—Tracing operation to perform. To specify more than one tracing operation, include multiple flag statements

  • all—Trace all events

  • packet—Trace packet and option decoding operations

  • state—Trace changes in state

level—Level of tracing to perform; also known as severity level. The option you configure enables tracing of events at that level and all higher (more restrictive) levels. You can specify any of the following levels:

  • all—Match messages of all levels.

  • error—Match error messages.

  • info—Match informational messages.

  • notice—Match notice messages about conditions requiring special handling.

  • verbose—Match verbose messages. This is the lowest (least restrictive) severity level; when you configure verbose, messages at all higher levels are traced. Therefore, the result is the same as when you configure all.

  • warning—Match warning messages.

  • Default: error

match regular-expression—(Optional) Refine the output to include lines that contain the regular expression.

no-remote-trace—Disable remote tracing.

no-world-readable—(Optional) Disable unrestricted file access.

size maximum-file-size—(Optional) Maximum size of each trace file. By default, the number entered is treated as bytes. Alternatively, you can include a suffix to the number to indicate kilobytes (KB), megabytes (MB), or gigabytes (GB). If you specify a maximum file size, you also must specify a maximum number of trace files with the files option.

  • Syntax: sizek to specify KB, sizem to specify MB, or sizeg to specify GB

  • Range: 10240 through 1073741824

world-readable—(Optional) Enable unrestricted file access.

Required Privilege Level

trace—To view this statement in the configuration.

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

Release Information

Statement introduced in Junos OS Release 11.4.