Definition

Firewall filters in Juniper Junos are stateless packet filters that act pretty much like the access lists in Cisco IOS, IOS XE and NX-OS. Once configured, they must be assigned in the input or output direction of one or more interfaces to become effective.

Example scenario: preventing ping packets to be initiated from one direction while allowing the other direction

Topology

R1:ge-0/0/5(.1) <— 10.10.7.0/30 —> (.2)ge-0.0.1:R5

Configuration

On R5: