firehol-modifiers(5)

💖 firehol-modifiers — the page from firehol-modifiers(5) 💖

okay bestie, sit DOWN, because this one is short but it's giving main character energy for your firewall rules. 🎀

✨ NAME ✨

firehol-modifiers — pick whether your stuff runs on IPv4 or IPv6, or both, no cap

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🌈 SYNOPSIS 🌈

ipv4 definition-or-command argument...

ipv6 definition-or-command argument...

[both] definition-or-command argument...

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🦋 DESCRIPTION 🦋

okay so here's the vibe: when you slap a modifier in front of any command or definition, you're telling it to apply to IPv4 only or IPv6 only. that's it. that's the whole thing. 💅

and if you don't use a modifier? then your interface and router definitions — plus any commands that come before either of those — get applied to BOTH IPv4 and IPV6. both. periodt. 👑

lowkey important: commands that live inside an interface or router just inherit whatever the enclosing definition is doing. so like, you cannot create an IPv4 command inside an IPv6 interface or router, and you can't do IPv6 inside an IPv4 one either. nope. not happening. 🚫

here are the examples, exactly as written, because I would never mess with them:

interface eth0 myboth src4 192.0.2.0/24 src6 2001:DB8::/24
  ipv4 server http accept
  ipv6 server http accept

ipv4 interface eth0 my4only src 192.0.2.0/24
  server http accept

ipv6 interface eth0 my6only src 2001:DB8::/24
  server http accept

see how the server http accept inside the ipv4 interface just knows it's IPv4? that's the enclosing-definition behaviour, and it's honestly iconic. 🧚

also!! lots of definitions and commands have explicitly named variants — like router4, router6, and router46 — which you can use as shorthand instead of slapping a modifier out front. obsessed with the efficiency honestly. 🍓

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👑 SEE ALSO 👑

• firehol(1) — FireHOL program
• firehol.conf(5) — FireHOL configuration
• firehol-interface(5) — interface definition
• firehol-router(5) — router definition
• firehol-policy(5) — policy command
• firehol-protection(5) — protection command
• firehol-server(5) — server, route commands
• firehol-client(5) — client command
• firehol-group(5) — group command
• firehol-iptables(5) — iptables helper
• firehol-masquerade(5) — masquerade helper
• FireHOL Website
• FireHOL Online PDF Manual
• FireHOL Online Documentation

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🌸 AUTHORS 🌸

FireHOL Team. shoutout to the team, they ate. 🫶

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and that's the whole page bestie!! this was FireHOL Reference, built 13 Apr 2025, sitting pretty at version 3.1.8. mwah. 💜✨