Following Pi-Hole's update to v6 that creates amazing lags and performance issues:

dig google.com @8.8.8.8 | grep time 
;; Query time: 7 msec
dig google.com @192.168.1.1 -p 53 | grep time #SwisscomBox
;; Query time: 10 msec
dig google.com @192.168.1.10 | grep time #Raspberry Pi 2...
;; Query time: 1316 msec
dig google.com @192.168.1.11 | grep time #BeagleBoneBlack
;; Query time: 12 msec

Now the same after moving both to AdGuard:

dig google.com @8.8.8.8 | grep time
;; Query time: 10 msec
dig google.com @192.168.1.1 | grep time 
;; Query time: 6 msec
dig google.com @192.168.1.10 | grep time
;; Query time: 13 msec
dig google.com @192.168.1.11 | grep time
;; Query time: 10 msec
dig google.com @192.168.1.15 | grep time #Docker container see below
;; Query time: 4 msec

~straightforward once you have the correct archive…

• Raspberry Pi:

  wget https://static.adguard.com/adguardhome/release/AdGuardHome_linux_armv6.tar.gz

• BeagleBoneBlack:

  wget AdGuardHome_linux_armv7.tar.gz

tar xvzf AdGuardHome_linux*.tar.gz
cd AdGuardHome
./AdGuardHome -s install

And voilà … : might be better to put in /opt
Once installed, go to http://IP of your device:3000 to start the setup
In Settings/DNS Settings, put the IP of unbound + some other failover DNS:

 127.0.0.1:5335
 9.9.9.9
 1.1.1.1

Enjoy your new DNS

Here is a Docker version:
it's a container with a fixedIP ≠ from the docker server

docker network create -d macvlan   --subnet=192.168.1.0/24 --gateway=192.168.1.1 -o parent=eno1  my_macvlan

git clone https://github.com/hat3ph/docker-adguard-unbound.git
cd docker-adguard-unbound
vi docker-compose.yml

services:
  adguard-unbound:
    container_name: adguard-unbound
    image: ghcr.io/hat3ph/adguard-unbound:latest
    restart: unless-stopped
    hostname: adguard-unbound
    volumes:
      - "./adguard/opt-adguard-work:/opt/adguardhome/work"
      - "./adguard/opt-adguard-conf:/opt/adguardhome/conf"
      - "./unbound:/opt/unbound"
    networks:
      my_macvlan:
        ipv4_address: 192.168.1.15  # statically assign the desired LAN IP
 
networks:
  my_macvlan:
    external: true

mkdir -p ./adguard/opt-adguard-work
mkdir -p ./adguard/opt-adguard-conf
mkdir -p ./unbound
 
docker compose up -d

then finish the setup in http://192.168.1.15:3000
DNS of unbound is in unbound/unbound.conf: 127.0.0.1:5053 → to be put in Settings/DNS Settings

 vi ./unbound/unbound.conf

        prefetch: yes
        prefetch-key: yes
        msg-cache-size: 128m
        rrset-cache-size: 256m
        # Minimum caching time for any record (in seconds)
        cache-min-ttl: 300

docker rm -f adguard-unbound
docker compose up -d

Better Host perfs

sysctl -w net.core.rmem_max=26214400
sysctl -w net.core.wmem_max=26214400
sysctl -w net.ipv4.tcp_rmem="4096 87380 26214400"
sysctl -w net.ipv4.tcp_wmem="4096 16384 26214400"

Improve cache & speed :

vi /opt/AdGuardHome/conf/upstream-dns.txt 
systemctl restart AdGuardHome

#DNS.WATCH
84.200.69.80
84.200.70.40
#OpenDNS
#208.67.222.222
#208.67.220.220