What it does
firewalld manages firewall policy through zones, with separate runtime and persistent configurations and interfaces for applications.
firewalld's runtime and permanent configurations let an administrator evaluate a rule without immediately making it survive every restart. Once the intended behavior is understood, the configuration can be made persistent. Assign the correct trust zone to an interface or connection before opening services. Record whether a change is temporary or permanent, especially during troubleshooting. The documented D-Bus interface also lets applications request changes, which should fit the host's policy rather than bypass it.
Strengths
- Separate temporary and persistent firewall configuration
- Zone-based trust model
Best for
- Linux administrators managing host firewall rules
Sources
- Home | firewalld (Oct 26, 2026)