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Juniper Networks Certified Associate, Junos (JNCIA-Junos) JN0-106 · Domain 7: Routing policy and firewall filters

Applying filters to interfaces (input/output) and to lo0 to protect the RE

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Last reviewed September 25, 2026 · Leer en español

A firewall filter does nothing until you apply it. You apply filters to a logical interface (unit) under the protocol family, choosing a direction. input filters packets arriving on the interface; output filters packets leaving it. You can apply one input and one output filter per family on an interface, or use input-list and output-list to apply several filters in sequence.

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