https://www.plixer.com/blog/scrutinizer/juniper-srx-series-gateway-supports-j-flow/
1. Enable sampling on desired interface(s) and directions:
set interfaces ge-0/0/0 unit 0 family inet sampling input
set interfaces ge-0/0/0 unit 0 family inet sampling output
2. Specify sampling rate and where to send the J-Flow data:
- #Specify sampling rate.
Caution:
- Activation of Flow collection can have a significant impact on the performance of the SRX device. The smaller the sample rate, the bigger the impact . A sampling input rate of 1 is
not
- recommended.
set forwarding-options sampling input rate 100
#Specify UDP port number of host collecting cflowd packetsset forwarding-options sampling family inet output flow-server 192.168.1.5 port 9996
#Specify version format: 5, 8 or 500 (ASN 500)set forwarding-options sampling family inet output flow-server 192.168.1.5 version 5
For a sample configuration, please check our FAQ archive for enabling flow export on a Juniper router.