Flow Monitoring and Discard Accounting Configuration Guidelines > Minimum Traffic Sampling or Forwarding Configuration

To configure traffic sampling on a logical interface, you must perform at least the following tasks:

• Create a firewall filter to apply to the logical interfaces being sampled by including the filter statement at the [edit firewall family family-name] hierarchy level. In the filter then statement, you must specify the action modifier sample and the action accept.

filter filter-name {

    term term-name {

        then {

            sample;

            accept;

        }

    }

}

For more information about firewall filter actions and action modifiers, see the JUNOS Policy Framework Configuration Guide.

• Apply the filter to the interfaces on which you want to sample traffic by including the address and filter statements at the [edit interfaces interface-name unit logical-unit-number family family-name] hierarchy level:

address address {

    destination destination-address;

}

filter {

    input filter-name;

} 

• Enable sampling and specify a nonzero sampling rate by including the sampling statement at the [edit forwarding-options] hierarchy level:

sampling {

    input {

        family inet {

            max-packets-per-second number;

            rate number;

        }

    }

}