Resolving gets stuck random (RPI)

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1

Hey folks,

I want to migrate from the pihole-unbound-all-in-one-docker to a seprate installation, to be able to keep the images up to date by following this guide: https://www.youtube.com/watch?v=Y3nm519xHfw&t=449s

I am getting strange errors like this:
[✗] Failed to resolve internodal-section.000webhostapp.com on eth1 (172.21.0.2)

Sometimes just one, sometimes more and always on an different docker-IP / devices. Yesterday I've got also hundrets of "Status unknown" in the query log, browsing got stuck at this time as well. I thought, this behaviour is in relation with the resolve-errors, but I am not sure.

Here's the compose file (networkrelated stuff is not yet outsourced to the env-file.)

networks:
  dns_net:
    driver: bridge
    ipam:
        config:
        - subnet: 172.16.0.0/16
  proxy:
    external: true

services:
  pihole:
    container_name: pihole-stack-app
    hostname: pihole
    image: pihole/pihole:${PIHOLE_IMAGE_TAG}
    networks:
      dns_net:
        ipv4_address: 172.16.0.7
      proxy:
    ports:
      - ${PIHOLE_PORT_HOST_443:-443}:${PIHOLE_PORT_DOCKER_443:-443}/tcp
      - ${PIHOLE_PORT_HOST_53_TCP:-53}:${PIHOLE_PORT_DOCKER_53_TCP:-53}/tcp
      - ${PIHOLE_PORT_HOST_53_UDP:-53}:${PIHOLE_PORT_DOCKER_53_UDP:-53}/udp
      - ${PIHOLE_WEBPORT_HOST}:${PIHOLE_WEBPORT_DOCKER:-80}/tcp # Web-Access Port
      - ${PIHOLE_PORT_HOST_22:-22}/tcp # SSH
    environment:
      - TZ=${TZ}
      - WEBPASSWORD=${WEBPASSWORD}
      - PIHOLE_DNS_=${PIHOLE_DNS_}
      - VIRTUAL_HOST=${VIRTUAL_HOST}
    volumes:
      - /opt/docker_data/pihole-stack/pihole/_etc-pihole/:/etc/pihole/
      - /opt/docker_data/pihole-stack/pihole/_etc-dnsmasq.d/:/etc/dnsmasq.d/
    restart: unless-stopped
    labels:
      wud.tag.include: ^\d{4}\.\d{2}\.$
  unbound:
    container_name: pihole-stack-unbound
    image: mvance/unbound-rpi:${UNBOUND_IMAGE_TAG}
    networks:
      dns_net:
        ipv4_address: 172.16.0.8
    volumes:
      - /opt/docker_data/pihole-stack/unbound/_opt/unbound/etc/unbound:/opt/unbound/etc/unbound

    ports:
      - 5053:53/tcp
      - 5053:53/tcp
    healthcheck:
      test: ["NONE"]
    restart: unless-stopped
    labels:
      wud.tag.include: ^\d+\.\d+\.\d+$

Does anyone have an idea?
Cheers,

2

Where do you observe that message?