Configuring flow exports on Juniper Routers

This section gives the steps to configure cflowd/J-Flow export on Juniper devices.To enable sampling and to export the flow records to specific destination address, follow the below command:

forwarding-options {
        sampling {
           input {
               family inet {
                   rate 100;
               run-length 9;
            max-packets-per-second 7000;
        }
    }
    {
        cflowd <destination address>{
                   port <port number>;
                        source-address <source address>;
                        version <version number>;
                    no-local-dump;
                autonomous-system-type origin;
            }
        }
    }
}

To enable packet sampling on the particular interface(s), from which flow analyzis to be done follow the below steps:

interfaces {
    ge-1/3/0 {
        vlan-tagging;
        unit 101 {
            vlan-id 101;
            family inet {
                sampling {
                    input;
                    output;
                }
                address 206.80.253.26/25
            }
        }
    }
}

For more information, refer here and this link (to configure V9 Template record).