By default the policyd is using IPv6. This needs to be forced to use IPv4 since the VPS I’m using doesn’t seem to have IPv6 enabled

  1. nano /etc/supervisor/conf.d/policyd.conf

  2. Replace command=/srv/modoboa/env/bin/python /srv/modoboa/instance/manage.py policy_daemon with command=/srv/modoboa/env/bin/python /srv/modoboa/instance/manage.py policy_daemon --host 127.0.0.1