how to verify Pipelined TCP and DNSCOOKIE

Tony Finch dot at
Tue Sep 4 14:13:00 UTC 2018

Rodrigo Reyna <usesforskypeonly at> wrote:

> I don't know how to confirm [Pipelined TCP queries(RFC7766)].
> Specifically, please tell me if there is a method to check with the command
> such as dig for the server on which BIND 9.11 is running.

`mdig` comes with BIND and does multiple concurrent queries, so you can
check pipelining behaviour like this:

$ rndc flush; mdig +tcp +noall +answer @::1 \ \ \ \ \ \

A good selection of sites near and far should nicely demonstrate
out-of-order replies. If you don't flush the cache first then you'll get
the answers in an effectively random order.

For years I have used `adns` for bulk concurrent queries, and it's really
good at pipelining queries over a TCP connection.

> The other is about [DNSCOOKIE].

Dunno this one I'm afraid.

f.anthony.n.finch  <dot at>
a fair, free and open society

More information about the bind-users mailing list