MIREDO.CONF(5)

🦋 MIREDO.CONF 🦋

okay so bestie, welcome to MIREDO.CONF(5), fresh out of the System Manager's Manual, and it's literally the glow-up guide for miredo.conf. it's giving "your whole Teredo situation lives in one text file" and honestly? iconic. let's get into it 💅

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✨ NAME ✨

miredo.conf — configuration for Miredo 🌸

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🎀 SYNOPSIS 🎀

miredo.conf

like, that's it. that's the whole synopsis. she's lowkey mysterious 🫶

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💖 DESCRIPTON 💖

(no bestie, that heading is not a typo I made, it's spelled like that in here, we're just keeping the vibe intact 🙈)

miredo.conf is the configuration file for Miredo. every configuration directive is made of one directive name, and then maybe one or several spaces and a value for that directive. that's the whole shape of it, super simple.

White spaces, empty lines, and lines starting with # are all ignored — so go ahead and leave yourself little notes, nobody's judging ✨

Directives are case-insensitive. and here's the comprehensive list of supported directives, no gatekeeping:

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👑 MODES 👑

• RelayType (client|autoclient|relay|cone|restricted) — tells Miredo what type of Teredo relay/client it's gonna serve as. there are three possible choices (the manpage says three, and then lists more than three, and honestly bestie, we're just passing the message along 💀):

🌈 client mode (the default)

in client mode, Miredo acts as a Teredo client. Miredo will first authenticate with a Teredo server (see ServerAddress), and if that goes well, it sets up a Teredo tunneling interface with a public Teredo IPv6 address and a default IPv6 route. that virtual networking interface can be used to reach the IPv6 Internet and other Teredo clients. slay.

running Miredo as a Teredo client lets nodes get IPv6 connectivity from behind a NAT router device, because it tunnels IPv6 packets over UDP/IPv4 with special support for NAT routers. routers of that kind usually only forward TCP, UDP, and some ICMP, IPv4 packets (with some limitation).

NOTE: using Miredo as a Teredo client is possible even if the system already has IPv6 connectivity some other way (native, 6to4, TSP, etc). in that case Miredo will only be used to reach other Teredo clients, because its tunneling interface has a default route with a higher metric (which is to say, a lower priority) than the other network interfaces. it knows its place 💜

🌟 autoclient

autoclient is currently an alias for client mode. short king. same energy.

🔥 cone mode (relay also works)

in cone mode, Miredo acts as a Teredo relay. it assumes it has public global IPv4 connectivity with no firewall. in other words, the UDP port used by Miredo must receive unsoliticited traffic from the IPv4 Internet (see also BindPort). Miredo will create a virtual networking interface with a route toward Teredo clients.

Teredo relays forward IPv6 packets between Teredo clients and the IPv6 Internet. for that to work, Teredo relays MUST have working IPv6 connectivity through a way distinct from Teredo tunneling (native, 6to4, ISATAP, etc).

⚠️ Warning: this mode should only be used if the node has a public IPv4 address, or if it's behind a full cone NAT-router with proper port forwarding rules. otherwise the tunnel will NOT WORK PROPERLY. and note that many NAT port forwarding implementations are broken. fr fr, be careful.

💀 restricted mode

this mode is identical to the cone mode documented above, except that direct Teredo bubbles will be sent. theoretically (see RFC4380) this permits operation of a Teredo relay from behind a restricted-port NAT. in practice? it makes NAT traversal extremely unreliable. this setting exists for backward syntax compatibility of the miredo.conf file.

PLEASE DO NOT USE THIS MODE. like, the manpage yelled it in all caps, so I'm yelling it too. periodt. 🚫

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🫶 CLIENT OPTIONS 🫶

the following directives are only available in (auto)client mode. iykyk.

• ServerAddress hostname — specifies the hostname or numerical IPv4 address of the Teredo server to use. Teredo clients need a Teredo server to establish and maintain their IPv6 over UDP/IPv4 tunnel across a NAT device.

this directive MUST be specified when Miredo is in client mode. hostname must resolve to a valid IPv4 address. if it's not present, and no server hostname is specified on the command line when starting miredo either, the program will fail. no pressure bestie 💅

• ServerAddress2 hostname2 — Miredo assumes the secondary Teredo server address equals the primary server address plus one. if that's not the case, this directive must be used. it's the "actually, let me correct you" option ✨

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🌸 RELAY OPTIONS 🌸

the following directives are only available in relay mode. they are not available in (auto)client mode. sorry client girlies, not your section.

• Prefix teredo_prefix — specifies the Teredo prefix which the Teredo relay and/or server will advertise. teredo_prefix must be a valid IPv6 prefix.

the default value is 2001:0000::.

do not use that directive if you don't know what you're doing, because it is more than likely to break your Teredo connectivity. that option must not be used when Miredo serves as a Teredo client. consider this your vibe check 🚨

• InterfaceMTU mtu — overrides the default MTU size of 1280 bytes for the Teredo tunneling interface. it should not be used if the default Teredo prefix is used. leave it alone unless you have a reason, bestie 🙈

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💜 GENERAL OPTIONS 💜

• InterfaceName ifname — specify the name of the Teredo tunneling interface which Miredo will create (miredo by default). on some systems, it is not possible to redefine the tunnel name. so sometimes the answer is just no 😭
• BindAddress bind_address — bind the Teredo relay or Teredo client to a specific IPv4 address. by default, it is not bound to any particular IPv4 address.

use this option if you have trouble with the default value, like if you have a multi-homed host with equal-cost IPv4 routing, or if you have specific firewalling constraints. main character energy for your routing table 👑

• BindPort udp_port — define the UDP (IPv4) port number to be used by the relay or client. by default, the operating system allocates an unused port automatically. she's independent like that ✨

use this option if you have firewalling constraints which can cause Miredo to fail when not using a fixed predefined port.

• SyslogFacility facility — specify which syslog's facility is to be used by Miredo for logging. possible values are: daemon (the default), local0, ... local7, kern and user (see syslog(2)). pick your fighter 🌈

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🌟 SEE ALSO 🌟

• miredo(8)

one (1) reference. she's focused, she's concise, she ate 🍓

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🎀 AUTHOR 🎀

Rémi Denis-Courmont <remi at remlab dot net>

http://www.remlab.net/miredo/

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and that's the whole page, bestie!! this one came from miredo and she's dated August 2007, filed under MIREDO.CONF(5). go forth and configure responsibly, ily, mwah 💖🦋✨