Hi,
Lets get the first question out of the way, why run stubby in a container: I was hoping I wouldn’t have to compile from source (https://github.com/getdnsapi/getdns), but stubby isn’t in stable Debian or Raspbian repositories; although buster works fine with Debian (x86), this is not the case with Raspbian (arm) had issues with dhcpd & iptables, there are probably more issues, but I went back to stable before investigating further. The docker image compiles the source, but the build environment is predefined; so this is a good compromise for me.
The second question: Why use systemd to start the container, I like systemd and understand it; I don’t think any other reasons are required?
Setup
Install docker:
https://docs.docker.com/install/linux/docker-ce/debian/
sudo apt-get install git
git clone https://github.com/juzam/docker-getdns-stubby.git
cd ~/docker-getdns-stubby
The Dockerfile, pulls the development branch (which on 29/11/18, wouldn’t compile); Fixed by the developer 30/11/18, so we just need to change the exposed port:
mv Dockerfile Dockerfile.bak
nano or vi Dockerfile
FROM debian:buster MAINTAINER "Giovanni Angoli <[email protected]>" RUN apt-get update && apt-get install -y libyaml-dev libssl-dev libtool-bin autoconf git make && \ apt-get clean && \ rm -rf /var/lib/apt/lists/* RUN git clone https://github.com/getdnsapi/getdns.git WORKDIR getdns RUN git checkout develop && git submodule update --init && libtoolize -ci && autoreconf -fi && mkdir build WORKDIR build RUN ../configure --without-libidn --without-libidn2 --enable-stub-only --with-stubby && make && make install && ldconfig COPY stubby.yml /usr/local/etc/stubby/stubby.yml EXPOSE 53 CMD [ "/usr/local/bin/stubby" ]
If you wish to use to stubby with with pihole, then change EXPOSE to:
EXPOSE 5353
The stubby.yml provided this git repository uses IPv6, so needs updating if like myself using IPv4:
mv stubby.yml stubby.yml.bak
nano or vi stubby.yml
resolution_type: GETDNS_RESOLUTION_STUB
dns_transport_list:
- GETDNS_TRANSPORT_TLS
tls_authentication: GETDNS_AUTHENTICATION_REQUIRED
tls_query_padding_blocksize: 256
edns_client_subnet_private: 1
idle_timeout: 10000
round_robin_upstreams: 0
listen_addresses:
- 127.0.0.1@53
upstream_recursive_servers:
- address_data: 9.9.9.9
tls_auth_name: "dns.quad9.net"
If you wish to use to stubby with with pihole, I advise updating listen_addresses; as follows:
listen_addresses: - 127.0.2.2@5353
sudo docker build -t getdns-stubby .
Systemd
nano or vi /lib/systemd/system/docker-stubby.service
[Unit] Description=Stubby Container After=docker.service [Service] RemainAfterExit=yes ExecStart=/usr/bin/docker run -it -d --net=host getdns-stubby ExecStop=/home/pi/stop-stubby.sh Restart=on-failure RestartSec=5 [Install] WantedBy=multi-user.target
nano or vi /home/pi/stop-stubby.sh
#!/bin/bash /usr/bin/docker ps -q --filter ancestor=getdns-stubby | xargs -r docker stop
systemctl daemon-reload
systemctl enable docker-stubby
systemctl start docker-stubby
Testing
sudo apt-get install dnsutils
dig @127.0.0.1 quad9.net
expected result:
; <<>> DiG 9.10.3-P4-Raspbian <<>> @127.0.0.1 quad9.net ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51250 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 65535 ;; QUESTION SECTION: ;quad9.net. IN A ;; ANSWER SECTION: quad9.net. 1200 IN A 216.21.3.77 ;; Query time: 174 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Wed Nov 21 00:03:58 UTC 2018 ;; MSG SIZE rcvd: 63
If result is different, please check the above instructions.
Now what?
You could now use the host which you have setup as a dns resolver, but I suggest going beyond that and use pihole:
with stubby:
https://blog.sandchaschte.ch/en/pi-hole-with-dns-over-tls
Updating Stubby:
Every time docker-stubby. is started (including restarts), a new container is created, so when updating a clean up seems like a good idea; please follow the instructions below:
if using pihole:
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8) # DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN nameserver 127.0.0.1
I suggest adding another nameserver temporarily, for example quad9:
nano or vi /etc/resolv.conf
nameserver 9.9.9.9
If docker-stubby. is the only docker on the host, then:
sudo systemctl stop docker-stubby.service
sudo docker system prune (and y)
sudo docker image rm getdns-stubby
cd ~/docker-getdns-stubby
sudo docker build -t getdns-stubby .
sudo systemctl start docker-stubby.service
if not:
sudo systemctl stop docker-stubby
docker ps -a
remove all containers for getdns-stubby with sudo docker rm for example:
sudo docker rm bf3aa2dd8bb1
sudo docker image rm getdns-stubby
cd ~/docker-getdns-stubby
sudo docker build -t getdns-stubby .
sudo systemctl start docker-stubby.service
Thanks Tom.
P.S Please feel free to comment.
Sources:
https://github.com/juzam/docker-getdns-stubby
https://blog.sandchaschte.ch/en/pi-hole-with-dns-over-tls
https://pi-hole.net/
https://github.com/getdnsapi/getdns.git
https://docs.docker.com/install/