Configuring Sampling Instances

You can configure active sampling by defining a sampling instance that specifies a name for the sampling parameters and binding the instance name to a particular engine. This configuration enables you to define multiple named sampling parameter sets associated with multiple destinations (as many as the number of Packet Forwarding Engines in the chassis), with multiple protocol families per each sampling destination. This configuration is supported on MX Series, M120, M320, T640, T1600, and TX matrix routers and on the cflowd version5/8 and flow aggregation version 9 templates.

To implement this feature, you include the instance statement at the [edit forwarding-options sampling] hierarchy level:

instance instance-name { # named instances of sampling parametersinput { # input parameters common to all protocol families for this instancerate number;run-length number;}family (inet | inet6 | mpls) {input { # input parameters specific to the designated protocol familyrate number;run-length number;}output {flow-server server-name {version number { template template-name;}}interface {source-address address ;}}}}

The following considerations apply to the sampling instance configuration:

This configuration is supported on the IP version 4 (inet), IP version 6 (ipv6), and MPLS protocol families.
You can configure the rate and run-length options at the [edit forwarding-options sampling input] hierarchy level to apply common values for all families on a global basis. Alternatively, you can configure these options at the [edit forwarding-options sampling instance instance-name input] hierarchy level to apply specific values for each instance or at the [edit forwarding-options sampling instance instance-name family family input] hierarchy level to apply specific values for each protocol family you configure.

Note: The run-length and maximum-packet-length configuration statements are not supported on MX80 routers.

To associate the defined instance with a particular Packet Forwarding Engine, you include the sampling-instances statement at the [edit chassis fpc number] hierarchy level, as in the following example:

chassis {fpc 2 {sampling-instances samp1;}}

For more information about chassis configuration, see the Junos System Configuration Guide