From c9dd423bdf44812901f820fe87bd5ccfd8686e5b Mon Sep 17 00:00:00 2001 From: Remi Gacogne Date: Tue, 7 Jul 2020 14:36:23 +0200 Subject: [PATCH] auth: Document that two backends might have the same name/types As long as they are somehow kept in sync.. --- docs/appendices/backend-writers-guide.rst | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/docs/appendices/backend-writers-guide.rst b/docs/appendices/backend-writers-guide.rst index d3a846fdca..002ef194dc 100644 --- a/docs/appendices/backend-writers-guide.rst +++ b/docs/appendices/backend-writers-guide.rst @@ -246,6 +246,10 @@ and such. This limitation comes from the fact that PowerDNS uses ``ANY`` queries to fetch all types from the backend in one go and that it assumes that once one backend has returned records the other ones do not need to be called. + It is also possible to have two backends providing records for the same name + and types, for example if the first one does not support DNSSEC and the second + does, but that requires some mechanism outside of PowerDNS to keep records in + sync between the two backends. The first part of the code contains the actual logic and should be pretty straightforward. The second part is a boilerplate 'factory' class -- 2.47.2