- Pi-hole is a DNS sinkhole that can block ads and trackers for all devices on your network.
- Unbound is a validating, recursive, caching DNS resolver. It is designed to be fast and lean.
With this setup, a DNS query traverses: Client ➤ Pi-hole ➤ Unbound ➤ DNS Root Server / TLD Server / authoritative name server
➤ Install Pi-hole (if not already):
curl -sSL https://install.pi-hole.net | bashFollow the installation script, and confirm it works.
For local testing, you may want to install and use dig:
sudo apt install dnsutilsdig apple.com
At the end of the output, note: ;; SERVER: 192.168.178.2#53(192.168.178.2) - this is pi-hole responding on port 53 👍
➤ Install Unbound:
sudo apt install unboundDownload the current root hints file, this should be repeated every six months or so:
wget https://www.internic.net/domain/named.root -qO- | sudo tee /var/lib/unbound/root.hintsCreate a configuration file: sudo nano /etc/unbound/unbound.conf.d/pi-hole.conf
and paste the following text into the file...
server: # If no logfile is specified, syslog is used # logfile: "/var/log/unbound/unbound.log" verbosity: 0 interface: 127.0.0.1 interface: ::1 port: 5335 do-ip4: yes do-udp: yes do-tcp: yes # May be set to yes if you have IPv6 connectivity do-ip6: yes # You want to leave this to no unless you have *native* IPv6. With 6to4 and # Terredo tunnels your web browser should favor IPv4 for the same reasons prefer-ip6: yes # Use this only when you downloaded the list of primary root servers! # If you use the default dns-root-data package, unbound will find it automatically root-hints: "/var/lib/unbound/root.hints" # Trust glue only if it is within the server's authority harden-glue: yes # Require DNSSEC data for trust-anchored zones, if such data is absent, the zone becomes BOGUS harden-dnssec-stripped: yes # Don't use Capitalization randomization as it known to cause DNSSEC issues sometimes # see https://discourse.pi-hole.net/t/unbound-stubby-or-dnscrypt-proxy/9378 for further details use-caps-for-id: no # Reduce EDNS reassembly buffer size. # Suggested by the unbound man page to reduce fragmentation reassembly problems edns-buffer-size: 1472 # Perform prefetching of close to expired message cache entries # This only applies to domains that have been frequently queried prefetch: yes # One thread should be sufficient, can be increased on beefy machines. num-threads: 1 # Ensure kernel buffer is large enough to not lose messages in traffic spikes so-rcvbuf: 1m # Ensure privacy of local IP ranges private-address: 192.168.0.0/16 private-address: 169.254.0.0/16 private-address: 172.16.0.0/12 private-address: 10.0.0.0/8 private-address: fd00::/8 private-address: fe80::/10
Save and exit with: Ctrl-o Ctrl-x, then restart unbound:
sudo service unbound restartIf unbound fails to start, investigate why with: systemctl status unbound.service
When unbound starts without error, test it:
dig apple.com @127.0.0.1 -p 5335At the end of the output, note: ;; SERVER: 192.168.178.2#5335(192.168.178.2) - this is unbound (port 5335) 👍
➤ Back to Pi-hole. Either edit /etc/pihole/setupVars.conf to add the unbound server:
PIHOLE_DNS_1=127.0.0.1#5335PIHOLE_DNS_2=::1#5335
Or open the pihole web page, and goto Settings ➤ DNS and add the unbound server:
This Unbound configuration uses localhost#5335, we can also install NextDNS/Stubby on localhost#5353.
Note:
- The pi-hole.conf file above was sourced from the Pi-hole unbound documentation, which is more detailed.
- If you use Pi-hole regularly, remember to DONATE to the project to help with its continued development.
