[Pdns-users] ecs-add-for in recursor 4.3.0 failing to match IPv6 subnet

Kevin P. Fleming kevin at km6g.us
Sat May 2 12:36:59 UTC 2020

In my recursor I add EDNS client subnet information so that my auth
servers can process it in LUA records. My personal network has both
IPv4 ( and IPv6 (fd80:ae6b:5f43::/48) subnets.

Until this morning, I had this setting in recursor.conf:

ecs-add-for=, ::

The intention was to add EDNS client subnet information to all
queries. However, only queries which arrived on IPv4 got the correct
subnet added; queries which arrived on IPv6 got the default '127.0.0'

I changed the configuration line to:

ecs-add-for=, fd80:ae6b:5f43::/48

Now queries from both source subnets get the proper subnet added on
the way out, and the LUA record processing works as it should.

Unless I've misunderstood something, this appears to be a bug, as "::"
should have matched any incoming IPv6 address.

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