sFlow sampling with firewall filters

Junos OS Evolved supports sFlow packet sampling using ingress firewall filters. This feature enables selective packet sampling of traffic that matches specific firewall filter terms by using the sample action, providing granular traffic visibility while minimizing overall sampling overhead.

You configure packet sampling in a firewall filter term by using the set firewall family inet filter filer-name term term-name then sample command. You must combine this configuration with standard sFlow configuration under the set protocols sflow hierarchy, such as sample-rate and collector for configuring sFlow. 

When you configure the sample action in a firewall filter term, you cannot configure the discard or reject action in the same term.