[Cerowrt-devel] Fwd: [Babel-users] ANNOUNCE: babeld-1.12

Dave Taht dave.taht at gmail.com
Thu May 5 09:54:45 EDT 2022

I really like the 4 over 6 thing

---------- Forwarded message ---------
From: Juliusz Chroboczek <jch at irif.fr>
Date: Thu, May 5, 2022 at 5:06 AM
Subject: [Babel-users] ANNOUNCE: babeld-1.12
To: <babel-users at lists.alioth.debian.org>

Dear all,

Babeld 1.12 is available from


For more information about the Babel routing protocol, please see


This version implements v4-via-v6 routing, which allows an IPv6-only
router to route IPv4 completely transparently.  The work is due to
Théophile Bastian, Toke Høyland-Jørgensen, and myself.  The protocol is
described in RFC 9229, which has not been published yet; in the meantime,
you may find the final draft at


V4-via-v6 is enabled by default on Linux kernel 5.13 and later, which may
cause issues in your network:

  - IPv6-only routers will suddently start routing IPv4; if you rely on
    IPv6-only routers to isolate you from the IPv4 Internet, this will no
    longer work.  Please set up filtering rules and firewalls if you wish
    to be isolated from the Internet.

  - IPv6-only routers will suddenly start sending ICMPv4 messages using
    the IPv4 "dummy address"; please make sure your firewall
    rules let through ICMPv4 packets with source equal to lest
    you suffer from PMTUD blackholes.  (This applies even if you're not
    running Babel itself: filtering ICMPv4 packet-too-big is almost always
    a mistake.)

The full changelog follows.

5 May 2022: babeld-1.12

  * Implement v4-via-v6 routing (RFC 9229), which allows a router with
    IPv4 addresses only to route IPv4.  Thanks to Théophile Bastian.
  * Enable extended Netlink acks when available.
    Thanks to Toke Høyland-Jørgensen.
  * Fix restoring of interface configuration to avoid unbounded memory
    consumption.  Thanks to andrew-hoff.
  * Fix handling of deny filters in the install chain.

-- Juliusz

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FQ World Domination pending: https://blog.cerowrt.org/post/state_of_fq_codel/
Dave Täht CEO, TekLibre, LLC

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