Swarm Varnish

[webdobe]

Codebase

mounted codebase

Host OS

CentOS

Docker info output

Containers: 13
 Running: 7
 Paused: 0
 Stopped: 6
Images: 56
Server Version: 18.03.0-ce
Storage Driver: overlay
 Backing Filesystem: extfs
 Supports d_type: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
 Volume: local
 Network: bridge host macvlan null overlay
 Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: active
 NodeID: ibi1uendqffht27anh9109ozk
 Is Manager: true
 ClusterID: tcrprkgx4u8ol2hx53b68rigo
 Managers: 1
 Nodes: 4
 Orchestration:
  Task History Retention Limit: 5
 Raft:
  Snapshot Interval: 10000
  Number of Old Snapshots to Retain: 0
  Heartbeat Tick: 1
  Election Tick: 3
 Dispatcher:
  Heartbeat Period: 5 seconds
 CA Configuration:
  Expiry Duration: 3 months
  Force Rotate: 0
 Autolock Managers: false
 Root Rotation In Progress: false
 Node Address: 10.0.0.52
 Manager Addresses:
  10.0.0.52:2377
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: cfd04396dc68220d1cecbe686a6cc3aa5ce3667c
runc version: 4fc53a81fb7c994640722ac585fa9ca548971871
init version: 949e6fa
Security Options:
 seccomp
  Profile: default
Kernel Version: 3.10.0-693.21.1.el7.x86_64
Operating System: CentOS Linux 7 (Core)
OSType: linux
Architecture: x86_64
CPUs: 8
Total Memory: 2.708GiB
Name: OE-manager
ID: JNJN:DPCN:VIE4:3Z3M:F2NU:LBP5:W4JU:RVRL:NYDP:6JKJ:UXHH:3FYF
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

Docker compose file

services:
  php:
    image: wodby/drupal-php:7.1
    environment:
      PHP_SENDMAIL_PATH: /usr/sbin/sendmail -t -i -S mailhog:1025
      PHP_FPM_LOG_LEVEL: debug
    volumes:
      - /srv/www/html/staging/example/web:/var/www/html
      - /srv/www/docker/staging/example/settings.php:/var/www/html/sites/default/settings.php
    networks:
      - traefik
    deploy:
      placement:
        constraints:
          - node.role == worker
      replicas: 3

  nginx:
    image: wodby/drupal-nginx:7-1.13
    depends_on:
      - staging_example_php
    environment:
      NGINX_STATIC_CONTENT_OPEN_FILE_CACHE: "off"
      NGINX_ERROR_LOG_LEVEL: debug
      NGINX_BACKEND_HOST: staging_example_php
      NGINX_SERVER_NAME: staging.example.net
      NGINX_SERVER_ROOT: /var/www/html
    volumes:
      - /srv/www/html/staging/example/web:/var/www/html
    networks:
      - traefik
    deploy:
      placement:
        constraints:
          - node.role == worker
      replicas: 3
      labels:
        - 'traefik.backend=staging_example_nginx'
        - 'traefik.port=80'
        - 'traefik.frontend.rule=Host:nginx.staging.example.net'
        - 'traefik.docker.network=traefik_net'
        - 'traefik.backend.loadbalancer.method=wrr'
        - 'traefik.backend.loadbalancer.stickiness=true'
        - 'traefik.backend.loadbalancer.swarm=true'

  varnish:
    image: wodby/drupal-varnish:4.1-2.4.0
    depends_on:
      - staging_example_nginx
    environment:
      VARNISH_SECRET: secret
      VARNISH_BACKEND_HOST: staging_example_nginx
      VARNISH_BACKEND_PORT: 80
      VARNISH_EXCLUDE_URLS: ^(/update\\.php|/([a-z]{2}/)?admin|/([a-z]{2}/)?admin/.*|/([a-z]{2}/)?system/files/.*|/([a-z]{2}/)?flag/.*|.*/core/.*|.*/ajax/.*|.*/ahah/.*)$$
    networks:
      - traefik
    deploy:
      placement:
        constraints:
          - node.role == worker
      replicas: 3
      labels:
        - 'traefik.backend=staging_example_varnish'
        - 'traefik.port=6081'
        - 'traefik.frontend.rule=Host:staging.example.net'
        - 'traefik.docker.network=traefik_net'
        - 'traefik.backend.loadbalancer.method=wrr'
        - 'traefik.backend.loadbalancer.stickiness=true'
        - 'traefik.backend.loadbalancer.swarm=true'

Logs output

Varnish is saying it cannot make a choice between all the ip addresses for nginx (because one is getting created each node and they are all in my network)

I am not sure how to approach this issue. You can set multiple backends in varnish.vcl but since docker auto creates them I am kinda at a loss.

[webdobe]

I may have gotten around this. I am still testing but I believe I just needed to join nginx and varnish to there own network on each node not using the overlay driver. Then varnish only sees the one nginx.