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flag (Interfaces)



Hierarchy Level

Release Information

Statement introduced in Junos OS Release 10.1.


Define tracing operations for individual interfaces. To specify more than one tracing operation, include multiple flag statements.


  • all—Enable all interface trace flags.

  • event —Trace interface events.

  • cache—Enable interface flags for Web filtering cache maintained on the routing table.

  • enhanced—Enable interface flags for processing through Enhanced Web Filtering.

  • ipc—Trace interface IPC messages.

  • media—Trace interface media changes.

  • critical—Trace critical events.

  • major—Trace major events.

  • MTU is limited to 1518 on this interface.

  • Cache and enhanced options are applicable only to Enhanced Web Filtering.

Required Privilege Level

interface—To view this statement in the configuration.

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

Related Documentation