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Home Documentation Junos OS Junos CLI Reference CLI Reference T

Junos CLI Reference

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Junos CLI Reference
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then (Filters)

date_range 20-Nov-23
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Syntax

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then {
         action;
         action-modifiers;
}

Hierarchy Level

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[edit firewall family family-name filter filter-name term term-name]

Description

Configure a firewall filter action.

Options

action

Actions to accept, discard, or forward packets that match all conditions specified in a filter term.

Starting in Junos OS Release 18.4R1, two new actions – port-mirror and port-mirror-instance – are added for all match conditions, which enable selective port mirroring of MPLS traffic to a mirrored destination.

The port-mirror action enables port mirroring globally on the device, which applies to all Packet Forwarding Engines (PFEs) and associated interfaces.

The port-mirror-instance action enables you to customize each instance with different properties for input sampling and port mirroring output destinations, instead of having to use a single system-wide configuration for port mirroring.

Note:

  • You can configure only two port mirroring instances per Flexible PIC Concentrator (FPC) by including the instance port-mirror-instance-name statement at the [edit forwarding-options port-mirror] hierarchy level. You can then associate individual port mirroring instances with an FPC, PIC, or (Forwarding Engine Board (FEB) depending on the device hardware.

  • For both port-mirror and port-mirror-instance actions, the output interface must be enabled with Layer 2 family and not family MPLS (Layer 3) for the selective port mirroring feature to work.

action-modifiers

Additional actions to analyze, classify, count, or police packets that match all conditions specified in a filter term.

Required Privilege Level

firewall—To view this statement in the configuration.firewall-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 11.1.

Related Documentation

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