ferm
The facts below are what the maker publishes about ferm, checked and dated. Our editors have not written about it yet.
Plans and prices
From ferm's own pricing page, checked 11 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| ferm | Free | No paid plans or usage limits stated on the project page |
The facts
Each one read from ferm's own pages, with the date it was checked.
What it does
- Compilation
- The README says the package does not need to be compiled.checked 11 Oct 2026
- Configuration language
- ferm’s configuration language supports variables, functions, arrays, blocks, and including other files.checked 11 Oct 2026
- Dependencies
- Installation requires Perl, iptables including iptables-save and iptables-restore, and a kernel supporting netfilter.checked 11 Oct 2026
- Documentation
- The ferm(1) manual page provides documentation about ferm syntax, and the README suggests starting from example files.checked 11 Oct 2026
- Firewall domains
- Since version 2.0, ferm supports ip, ip6, arp, and Ethernet bridging tables.checked 11 Oct 2026
- Goal
- The project aims to make firewall rules easier to write and read.checked 11 Oct 2026
- Included files
- Configuration can include individual files, directories, wildcard matches, or shell command output.checked 11 Oct 2026
- Installation
- The README says the package does not need compilation and can be installed with make install.checked 11 Oct 2026
- Intended user
- The README describes ferm as a tool for firewall administrators who want to spend more time developing rules than implementing them.checked 11 Oct 2026
- Intended users
- The README describes ferm as a tool for firewall administrators who want to write and read firewall rules more easily.checked 11 Oct 2026
- Interactive mode
- The README recommends using interactive mode while applying rules to avoid locking yourself out of remote machines.checked 11 Oct 2026
- License
- The repository identifies ferm as GPL-2.0 licensed software.checked 11 Oct 2026
- Migration
- The included import-ferm script converts current firewall rules into a ferm configuration file.checked 11 Oct 2026
- Outbound control
- advancedchecked 22 Sep 2026
- Purpose
- ferm is a frontend for iptables that reads firewall rules from a structured configuration file and inserts them into the running kernel.checked 11 Oct 2026
- Remote safety
- Interactive mode asks for confirmation and restores the previous ruleset if there is no valid response before the timeout, which defaults to 30 seconds.checked 11 Oct 2026
- Requirements
- The documentation lists Linux 2.4 or newer with netfilter support, iptables, and Perl 5.6 as requirements.checked 11 Oct 2026
- Reusable rules
- Included files can be used to create libraries of commonly used structures and functions.checked 11 Oct 2026
- Rule direction
- bothchecked 22 Sep 2026
- Rule import
- The import-ferm script converts existing firewall rules into a ferm configuration file.checked 11 Oct 2026
- Rule installation
- Fast mode generates an iptables-save file and installs it with iptables-restore, and has been enabled by default since ferm 2.0.checked 11 Oct 2026
- Rule language
- Its configuration language supports variables, functions, arrays, blocks, and included files.checked 11 Oct 2026
- Support
- The documentation directs bug reports to the project's GitHub issues page.checked 11 Oct 2026
Where it runs
- Supported platforms
- linuxchecked 22 Sep 2026
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