mailu/docs/swarm/1.5

Install Mailu on a docker swarm

Prequisites

Swarm

You need to have a swarm running

In order to deploy Mailu on a swarm, you will first need to initialize it: The main command will be:

docker swarm init --advertise-addr <IP_ADDR>

See https://docs.docker.com/engine/swarm/swarm-tutorial/create-swarm/

If you want to add other managers or workers, please use:

docker swarm join --token xxxxx 

See https://docs.docker.com/engine/swarm/join-nodes/

You have now a working swarm, and you can check its status with:

core@coreos-01 ~/git/Mailu/docs/swarm/1.5 $ docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
xhgeekkrlttpmtgmapt5hyxrb     black-pearl         Ready               Active                                  18.06.0-ce
sczlqjgfhehsfdjhfhhph1nvb *   coreos-01           Ready               Active              Leader              18.03.1-ce
mzrm9nbdggsfz4sgq6dhs5i6n     flying-dutchman     Ready               Active                                  18.06.0-ce

Volume definition

For data persistance (the Mailu services might be launched/relaunched on any of the swarm nodes), we need to have Mailu data stored in a manner accessible by every manager or worker in the swarm. Hereafter we will use a NFS share:

core@coreos-01 ~ $ showmount -e 192.168.0.30
Export list for 192.168.0.30:
/mnt/Pool1/pv            192.168.0.0

on the nfs server, I am using the following /etc/exports

$more /etc/exports
/mnt/Pool1/pv -alldirs -mapall=root -network 192.168.0.0 -mask 255.255.255.0 

on the nfs server, I created the Mailu directory (in fact I copied a working Mailu set-up)

$mkdir /mnt/Pool1/pv/mailu

On your manager node, mount the nfs share to check that the share is available:

core@coreos-01 ~ $ sudo mount -t nfs 192.168.0.30:/mnt/Pool1/pv/mailu /mnt/local/

If this is ok, you can umount it:

core@coreos-01 ~ $ sudo umount /mnt/local/

Networking mode

On a swarm, the services are available (default mode) through a routing mesh managed by docker itself. With this mode, each service is given a virtual IP adress and docker manages the routing between this virtual IP and the container(s) provinding this service. With this default networking mode, I cannot get login working properly... As found in https://github.com/Mailu/Mailu/issues/375 , a workaround is to use the dnsrr networking mode at least for the front services.

The main consequence/limitation will be that the front services will not be available on every node, but only on the node where it will be deployed. In my case, I have only one manager and I choose to deploy the front service to the manager node, so I know on wich IP the front service will be available (aka the IP adress of my manager node).

Variable substitution

The docker stack deploy command doesn't support variable substitution in the .yml file itself (vut we still can use .env file to pass variables to the services). As a consequence we need to adjust the docker-compose file to :

• remove all variables : $VERSION , $BIND_ADDRESS4 , $BIND_ADDRESS6 , $ANTIVIRUS , $WEBMAIL , etc
• change the way we define the volumes (nfs share in our case)

Docker compose

A working docker-compose-stack.yml file is available here:

version: '3.2'

services:

  front:
    image: mailu/nginx:1.5
    env_file: .env
    ports:
      - target: 80
        published: 80
        mode: host
      - target: 443
        published: 443
        mode: host
      - target: 110
        published: 110
        mode: host
      - target: 143
        published: 143
        mode: host
      - target: 993
        published: 993
        mode: host
      - target: 995
        published: 995
        mode: host
      - target: 25
        published: 25
        mode: host
      - target: 465
        published: 465
        mode: host
      - target: 587
        published: 587
        mode: host
    volumes:
#      - "$ROOT/certs:/certs"
      - type: volume
        source: mailu_certs
        target: /certs
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  redis:
    image: redis:alpine
    restart: always
    volumes:
#      - "$ROOT/redis:/data"
      - type: volume
        source: mailu_redis
        target: /data
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  imap:
    image: mailu/dovecot:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/data:/data"
      - type: volume
        source: mailu_data
        target: /data
#      - "$ROOT/mail:/mail"
      - type: volume
        source: mailu_mail
        target: /mail
#      - "$ROOT/overrides:/overrides"
      - type: volume
        source: mailu_overrides
        target: /overrides
    depends_on:
      - front
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  smtp:
    image: mailu/postfix:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/data:/data"
      - type: volume
        source: mailu_data
        target: /data
#      - "$ROOT/overrides:/overrides"
      - type: volume
        source: mailu_overrides
        target: /overrides
    depends_on:
      - front
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  antispam:
    image: mailu/rspamd:1.5
    restart: always
    env_file: .env
    depends_on:
      - front
    volumes:
#      - "$ROOT/filter:/var/lib/rspamd"
      - type: volume
        source: mailu_filter
        target: /var/lib/rspamd
#      - "$ROOT/dkim:/dkim"
      - type: volume
        source: mailu_dkim
        target: /dkim
#      - "$ROOT/overrides/rspamd:/etc/rspamd/override.d"
      - type: volume
        source: mailu_overrides_rspamd
        target: /etc/rspamd/override.d
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  antivirus:
    image: mailu/none:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/filter:/data"
      - type: volume
        source: mailu_filter
        target: /data
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  webdav:
    image: mailu/none:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/dav:/data"
      - type: volume
        source: mailu_dav
        target: /data
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  admin:
    image: mailu/admin:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/data:/data"
      - type: volume
        source: mailu_data
        target: /data
#      - "$ROOT/dkim:/dkim"
      - type: volume
        source: mailu_dkim
        target: /dkim
      - /var/run/docker.sock:/var/run/docker.sock:ro
    depends_on:
      - redis
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  webmail:
    image: "mailu/roundcube:1.5"
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/webmail:/data"
      - type: volume
        source: mailu_data
        target: /data
    depends_on:
      - imap
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

  fetchmail:
    image: mailu/fetchmail:1.5
    restart: always
    env_file: .env
    volumes:
#      - "$ROOT/data:/data"
      - type: volume
        source: mailu_data
        target: /data
    logging:
      driver: none
    deploy:
      endpoint_mode: dnsrr
      replicas: 1
      placement:
        constraints: [node.role == manager]

volumes:
  mailu_filter:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/filter"
  mailu_dkim:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/dkim"
  mailu_overrides_rspamd:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/overrides/rspamd"
  mailu_data:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/data"
  mailu_mail:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/mail"
  mailu_overrides:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/overrides"
  mailu_dav:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/dav"
  mailu_certs:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/certs"
  mailu_redis:
    driver_opts:
      type: "nfs"
      o: "addr=192.168.0.30,nolock,soft,rw"
      device: ":/mnt/Pool1/pv/mailu/redis"

Deploy Mailu on the docker swarm

Run the following command:

docker stack deploy -c docker-compose-stack.yml mailu

See how the services are being deployed:

core@coreos-01 ~ $ docker service ls
ID                  NAME                                 MODE                REPLICAS            IMAGE                                     PORTS
ywnsetmtkb1l        mailu_antivirus                      replicated          1/1                 mailu/none:1.5
pqokiaz0q128        mailu_fetchmail                      replicated          1/1                 mailu/fetchmail:1.5

check a specific service:

core@coreos-01 ~ $ docker service ps mailu_fetchmail
ID                  NAME                IMAGE                 NODE                DESIRED STATE       CURRENT STATE         ERROR               PORTS
tbu8ppgsdffj        mailu_fetchmail.1   mailu/fetchmail:1.5   coreos-01           Running             Running 11 days ago

Remove the stack

Run the follwoing command:

core@coreos-01 ~ $ docker stack rm mailu