Yes, they come from the packages at deb.knot-dns.cz/knot (by adding `deb
https://deb.knot-dns.cz/knot/ jessie main` to
`/etc/apt/sources.list.d/knot.list` and running `sudo apt-get update`.
For me, running `apt-cache showpkg knot` shows (among other things):
Dependencies:
2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef - adduser (0 (null))
libdnssec4 (5 2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef) libknot6 (5
2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef) libzscanner1 (5
2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef) lsb-base (2 3.0-6) python (0
(null)) python-lmdb (0 (null)) python-yaml (0 (null)) init-system-helpers
(2 1.18~) libc6 (2 2.17) libedit2 (2 2.11-20080614) libgnutls-deb0-28 (2
3.3.0) libsystemd0 (0 (null)) liburcu2 (2 0.8.4) systemd (0 (null))
2.4.0-3 - adduser (0 (null)) libdnssec2 (5 2.4.0-3) libknot5 (5 2.4.0-3)
libzscanner1 (5 2.4.0-3) lsb-base (2 3.0-6) python (0 (null)) python-yaml
(0 (null)) init-system-helpers (2 1.18~) libc6 (2 2.17) libedit2 (2
2.11-20080614) libgnutls30 (2 3.5.0) libsystemd0 (0 (null)) liburcu4 (2
0.8.4) systemd (0 (null))
1.6.0-1 - knot-libs (5 1.6.0-1) libc6 (2 2.17) libidn11 (2 1.13) liblmdb0
(2 0.9.7) libssl1.0.0 (2 1.0.0) libsystemd0 (0 (null)) liburcu2 (2 0.8.4)
zlib1g (2 1:1.1.4) init-system-helpers (2 1.18~) adduser (0 (null)) systemd
(0 (null))
Weirdly, it looks like *no* version of knot from the knot-specific
repository has the fstrm or protobuf-c dependencies.  Nor do the versions
listed at 
https://packages.debian.org/stretch/knot or
https://packages.debian.org/jessie/knot , at least, not from the webpage.
This is consistent from what I remember setting this up with the earlier
version a few months ago; I definitely manually installed both libraries
(and several of *their* dependencies, and so on).
For what it's worth, I do have fstrm and protobuf-c installed on this
machine, both built manually, along with dnstap-ldns itself.  From what I
can tell by reading a test capture file from my other machine, dnstap is
installed correctly.  But knot doesn't seem to be able to deal with it in a
config file anymore.
If the support for dnstap got removed in knot 2.5, then I'll just use 2.4,
which is no problem, but it seems like a puzzling choice to remove it.  Is
there a newer, better way to capture the queries and responses?
Thanks again!
-Sarah
On Wed, Jun 14, 2017 at 1:44 PM Robert Edmonds <edmonds(a)debian.org> wrote:
  Sarah Scheffler wrote:
  Any idea what might be causing the issue here?
Did the syntax for
 mod-dnstap change or something?  Should I have installed from source?  I 
 do
  remember there being some special option you
needed to compile a 
 dependency
  with to use dnstap when I did this the first
time, but I couldn't find
 documentation for it when I looked for it. 
 Hi, Sarah:
 Where did you obtain your knot 2.5.1 package from? Looking at the
 official packages from deb.knot-dns.cz
 (
https://deb.knot-dns.cz/knot/pool/main/k/knot/), I see:
 $ dpkg-deb -I
 ./knot_2.5.1-2+0\~20170613103744.1+jessie\~1.gbp69c8ef_i386.deb
 [...]
  Depends: adduser, libdnssec4 (=
 2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef), libknot6 (=
 2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef), libzscanner1 (=
 2.5.1-2+0~20170613103744.1+jessie~1.gbp69c8ef), lsb-base (>= 3.0-6),
 python, python-lmdb, python-yaml, init-system-helpers (>= 1.18~), libc6 (>=
 2.17), libedit2 (>= 2.11-20080614), libgnutls-deb0-28 (>= 3.3.0),
 libsystemd0, liburcu2 (>= 0.8.4)
 [...]
 It doesn't have the fstrm and protobuf-c dependencies that would
 indicate dnstap support. Compare to the dependencies for the knot
 package in the Debian archive:
 $ apt-cache show knot/unstable | grep ^Depends:
 Depends: adduser, libdnssec2 (= 2.4.3-1), libknot5 (= 2.4.3-1),
 libzscanner1 (= 2.4.3-1), lsb-base (>= 3.0-6), python, python-yaml,
 init-system-helpers (>= 1.18~), libc6 (>= 2.17), libedit2 (>=
 2.11-20080614), libfstrm0 (>= 0.2.0), libgnutls30 (>= 3.5.0),
 libprotobuf-c1 (>= 1.0.1), libsystemd0, liburcu4 (>= 0.8.4)
 (Note the 'libfstrm0' and 'libprotobuf-c1' dependencies.)
 That is a pretty confusing error message to print if knot doesn't have
 dnstap support enabled, though.
 --
 Robert Edmonds
 edmonds(a)debian.org