Error installing mailman3 - failed to create network docker-mailman_mailman

[odhiambo]

Hello admins,

I have gotten stuck installing Mailman3 using Docker, to integrate with mailcow-dockernized. I am following three HOWTOS - [0] and [1], comparing the instructions with the ones given at https://asynchronous.in/docker-mailman/, and to be honest, I don't see much difference.

I get the following error:

root@srv1:/opt/docker-mailman# docker compose up -d
[+] Running 1/1
 ✘ Network docker-mailman_mailman  Error                                                                                                                                                                             
failed to create network docker-mailman_mailman: Error response from daemon: invalid pool request: Pool overlaps with other one on this address space

[0] This guide - https://docs.mailcow.email/third_party/mailman3/third_party-mailman3/. It says I create /opt/mailcow-dockerized/docker-compose.override.yml containing:

services:
  postfix-mailcow:
    volumes:
      - /opt/mailman:/opt/mailman
    networks:
      - docker-mailman_mailman

networks:
  docker-mailman_mailman:
    external: true

And the [0] refers to [1] https://github.com/g4rf/dockerized-mailcow-mailman, which also says I create the same file /opt/mailcow-dockerized/docker-compose.override.yml - but in this case the volume spec is different:

services:
  postfix-mailcow:
    volumes:
      - /opt/mailman/core/var/data/:/opt/mailman/core/var/data/
    networks:
      - docker-mailman_mailman

networks:
  docker-mailman_mailman:
    external: true

Because I am a n00b with Docker, I am wondering which one is the correct volume spec I should use. Is it "/opt/mailman:/opt/mailman" or the "/opt/mailman/core/var/data/:/opt/mailman/core/var/data/"?

And what might be the cause of the error that I am getting??

Thank you.

[maxking]

failed to create network docker-mailman_mailman: Error response from daemon: invalid pool request: Pool overlaps with other one on this address space

This is not related to mounts. This really is about networks. Sometimes, if there are older networks which you think have hijacked the addresses, you can find docker network ls:

maxking@portainer:~/Documents/docker-mailman$ docker network ls
NETWORK ID     NAME                                                                      DRIVER    SCOPE
9189bbebd049   GITEA-ACTIONS-TASK-744_WORKFLOW-Update-DNS_JOB-deploy-deploy-network      bridge    local
a53bb263c479   GITEA-ACTIONS-TASK-806_WORKFLOW-Update-DNS_JOB-deploy-deploy-network      bridge    local
9840cf763294   GITEA-ACTIONS-TASK-849_WORKFLOW-Update-DNS_JOB-deploy-deploy-network      bridge    local
242ac8523153   GITEA-ACTIONS-TASK-2832_WORKFLOW-Update-DNS_JOB-deploy-deploy-network     bridge    local
d8d6587f3d94   GITEA-ACTIONS-TASK-8774_WORKFLOW-Update-Caddy_JOB-deploy-deploy-network   bridge    local
dfb9a77b8c27   GITEA-ACTIONS-TASK-8775_WORKFLOW-Update-Caddy_JOB-deploy-deploy-network   bridge    local
c8d874293437   GITEA-ACTIONS-TASK-8776_WORKFLOW-Update-DNS_JOB-deploy-deploy-network     bridge    local
39a61d602622   GITEA-ACTIONS-TASK-9876_WORKFLOW-Update-Caddy_JOB-deploy-deploy-network   bridge    local
4b838485814b   bridge                                                                    bridge    local
97bf89124fcb   docker-mailman_mailman                                                    bridge    local
318e8b0c1d2f   docker_gwbridge                                                           bridge    local
92afd42e293f   fusion-rss_default                                                        bridge    local
5e68d7a44766   host                                                                      host      local
q9faj5qztqr1   ingress                                                                   overlay   swarm
441d3cf1fa4f   it-tools_default                                                          bridge    local
4edbe9c0a0b7   jiotvgo_default                                                           bridge    local
543b0b9e686b   macvlan                                                                   macvlan   local
7ae5488a41bd   macvlan-configs                                                           null      local
c7cd73b37fdd   none                                                                      null      local

And maybe delete unused one like

maxking@portainer:~/Documents/docker-mailman$ docker network rm GITEA-ACTIONS-TASK-744_WORKFLOW-Update-DNS_JOB-deploy-deploy-network
GITEA-ACTIONS-TASK-744_WORKFLOW-Update-DNS_JOB-deploy-deploy-network

For using with mailcow, you probably need to mount /opt/mailman/core/var/data/:/opt/mailman/core/var/data/ into mailcow container so it can actually figure out the routes.

In the mailman, you should mount /opt/mailman:/opt/mailman instead.