I'm intending to use pihole for DNS requests and its admin interface. I have a (partially) working configuration and a malfunctioning configuration:
Working
Configuration
- deploy pihole on docker swarm over a custom overlay network
- create custom route in traefik by defining dynamic configuration, pointing to host
pihole_pihole:80 - frontend is accessible through
http://pihole.traefik/admin
Drawback
- load balancing is done through docker swarm and is random, each call ends up at a different pihole node, making it impractical
Malfunctioning
Configuration
- create the traefik integration (swarm mode) through docker labels
- traefik picks this up correctly, creating route and service
- having traefik do the load balancing, I can now use sticky sessions to make sure I remain connected to the same node
Problem
I'm getting timeouts when getting http://pihole.traefik/admin. Only once in a blue moon I get a response . The system stays responsive for 2 seconds and then becomes inactive again. I don't see relevant error logs on the pihole containers or traefik itself, so I'm not sure where I'm going wrong here.
System
- Docker version 19.03.12-ce, build 48a66213fe
- Swarm enabled, three nodes
The functioning traefik configuration is super basic, so I'll leave that out. Below is my pihole compose file, including the labels that I use in the malfunctioning scenario. Any ideas about why my setup is failing are greatly appreciated, I've been staring at this problem for a while now and I'm not sure where to go next.
version: "3.5"
services:
pihole:
image: pihole/pihole:latest
hostname: '{{.Node.Hostname}}'
ports:
- "53:53/tcp"
- "53:53/udp"
environment:
TZ: 'Europe/Brussels'
WEBPASSWORD: 'dddd'
# swarm does not support cap_add, this reverts to previous behaviour
FTL_CMD: 'debug'
DNSMASQ_LISTENING: 'all'
volumes:
- '/srv/pihole/etc-pihole/:/etc/pihole/'
- '/srv/pihole/etc-dnsmasq.d/:/etc/dnsmasq.d/'
dns:
- 127.0.0.1
- 8.8.8.8
deploy:
replicas: 2
restart_policy:
condition: on-failure
# using these labels when trying the malfunctioning scenario (route through traefik docker swarm integration)
#labels:
#traefik.enable: 'true'
#traefik.http.services.pihole.loadbalancer.server.port: 80
#traefik.http.services.pihole.loadbalancer.sticky.cookie: "true"
#traefik.http.routers.pihole.rule: "Host(`pihole.traefik`)"
#traefik.http.routers.pihole.service: "pihole"
#traefik.http.routers.pihole.entrypoints: "web"
placement:
constraints:
- "node.labels.dns==true"
networks:
default:
external: true
name: frontend