問題文
An administrator adds a rule with the zone-based firewall command and confirms the port is open, but after a service reload the port is closed again. What was omitted?
選択肢
- The zone was not activated, so the rule applied to a zone that no interface uses, and the reload then discards a rule that had only ever governed an idle zone.
- The rule needs a matching outbound rule, without which the inbound rule is removed at the next reload, and the pair must be declared together for either direction to persist.
- The service must be stopped before rules are added, because rules added while the service is running are held in a staging area that is discarded when the service reloads its configuration, and there is no way to promote them.
- The rule was added to the runtime configuration only, so it must also be written to the permanent configuration to survive a reload.