JUNOS INTEGRATION

Documentation to integrate FastNetMon with inline jflow using Juniper MX Series routers (MX5, MX10, MX40, MX80, MX104, MX120, MX240, MX480, MX960).

In this example, we use rate=500. It works well for amount of traffic from  100 Mbits/s. But you can increase to rate=1000, depending on your traffic.

For FastNetMon Community you need to change fastnetmon.conf netflow_sampling_ratio with same rate you setup on your MX router.

For FastNetMon Advanced you could change sampling value this way:

sudo fcli set main netflow_sampling_ratio 500
sudo fcli commit

Our topology is two MX80 routers, named r1 and r2. From each router connected directly to FastNetMon server.

FastNetMon server has 2 interfaces: 10.50.1.2/30 – connected to r1 10.50.1.6/30 – connected to r2 c R1 has 1 transit connected to ge-1/0/0.0 R2 has 1 transit connected to ge-1/0/0.0

Setting sampling on transit interfaces. Run that on those interfaces on each router.

set interfaces ge-1/0/0.0 family inet sampling input

Check interfaces configuration:

r1# show interfaces ge-1/0/4  
unit 0 {
    description netflow-collector;
    family inet {
        address 10.50.1.1/30;
    }
}



r1# show interfaces ge-1/0/4 | display set 
set interfaces ge-1/0/4 unit 0 description netflow-collector
set interfaces ge-1/0/4 unit 0 family inet address 10.50.1.1/30

r2# show interfaces ge-1/0/4  
unit 0 {
    description netflow-collector;
    family inet {
        address 10.50.1.5/30;
    }
}
r2# show interfaces ge-1/0/4 | display set 
set interfaces ge-1/0/4 unit 0 description netflow-collector
set interfaces ge-1/0/4 unit 0 family inet address 10.50.1.5/30

Now add templates configuration on r1 and r2. Take care of flow-active-timeout and flow-inactive-timeout it should be less than average_calculation_time.

You could set new average_calculation_time using configuration option in fastnetmon.conf in FastNetMon Community.

For FastNetMon Advanced you could use command line interface to configure it:

sudo fcli set main average_calculation_time 30
sudo fcli set main average_calculation_time_for_subnets 30
sudo fcli set main average_calculation_time_for_hostgroups 30
sudo fcli commit

Full configuration:

set services flow-monitoring version-ipfix template ipv4 flow-active-timeout 30
set services flow-monitoring version-ipfix template ipv4 flow-inactive-timeout 30
set services flow-monitoring version-ipfix template ipv4 template-refresh-rate packets 1000
set services flow-monitoring version-ipfix template ipv4 template-refresh-rate seconds 30
set services flow-monitoring version-ipfix template ipv4 option-refresh-rate packets 1000
set services flow-monitoring version-ipfix template ipv4 option-refresh-rate seconds 30
set services flow-monitoring version-ipfix template ipv4 ipv4-template
set chassis tfeb slot 0 sampling-instance ipfix


flow-monitoring {
    version-ipfix {
        template ipv4 {
            flow-active-timeout 30;
            flow-inactive-timeout 30;
            template-refresh-rate {
                packets 1000;
                seconds 10;
            }
            option-refresh-rate {
                packets 1000;
                seconds 10;
            }
            ipv4-template;
        }
    }
}

slot 0 {
    sampling-instance ipfix;
}

Now setup ipfix exports:

r1# show forwarding-options 
sampling {
    instance {
        ipfix {
            input {
                rate 500;
            }
            family inet {
                output {
                    flow-server 10.50.1.2 {
                        port 2055;
                        version-ipfix {
                            template {
                                ipv4;
                            }
                        }
                    }
                    inline-jflow {
                        source-address 10.50.1.1;
                    }
                }
            }
        }
    }
}

r1# show forwarding-options | display set 
set forwarding-options sampling instance ipfix input rate 500
set forwarding-options sampling instance ipfix family inet output flow-server 10.50.1.2 port 2055
set forwarding-options sampling instance ipfix family inet output flow-server 10.50.1.2 version-ipfix template ipv4
set forwarding-options sampling instance ipfix family inet output inline-jflow source-address 10.50.1.1


r2# show forwarding-options 
sampling {
    instance {
        ipfix {
            input {
                rate 500;
            }
            family inet {
                output {
                    flow-server 10.50.1.6 {
                        port 2055;
                        version-ipfix {
                            template {
                                ipv4;
                            }
                        }
                    }
                    inline-jflow {
                        source-address 10.50.1.5;
                    }
                }
            }
        }
    }
}

r2# show forwarding-options | display set 
set forwarding-options sampling instance ipfix input rate 500
set forwarding-options sampling instance ipfix family inet output flow-server 10.50.1.6 port 2055
set forwarding-options sampling instance ipfix family inet output flow-server 10.50.1.6 version-ipfix template ipv4
set forwarding-options sampling instance ipfix family inet output inline-jflow source-address 10.50.1.5

If you still have inaccurate traffic with Juniper MX, please check our guide about fine tuning for flow tables.