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.