I found the problem. Thanks for your help: As mailman3 via docker, consists of 2 independent containers (mailman-core & web) the templates, the runner used a wrong url when looking for templates. after adjusting my templates via SQL, all is fine now:
# sqlite3 /opt/mailman/core/var/data/mailman.db "SELECT * FROM template;" 1|list:user:notice:probe|cubewerk.de| http://localhost:8000/postorius/api/templates/domain/cubewerk.de/list:user:notice:probe|| 3|list:member:regular:footer|cubewerk.de| http://localhost:8000/postorius/api/templates/domain/cubewerk.de/list:member:regular:footer|| 4|list:member:regular:footer|lists.cubewerk.de| http://localhost:8000/postorius/api/templates/domain/lists.cubewerk.de/list:member:regular:footer|| sqlite3 /opt/mailman/core/var/data/mailman.db "UPDATE template SET uri = REPLACE(uri, 'localhost:8000', '172.18.0.3:8000');" # sqlite3 /opt/mailman/core/var/data/mailman.db "SELECT * FROM template;" 1|list:user:notice:probe|cubewerk.de| http://172.18.0.3:8000/postorius/api/templates/domain/cubewerk.de/list:user:notice:probe|| 3|list:member:regular:footer|cubewerk.de| http://172.18.0.3:8000/postorius/api/templates/domain/cubewerk.de/list:member:regular:footer|| 4|list:member:regular:footer|lists.cubewerk.de| http://172.18.0.3:8000/postorius/api/templates/domain/lists.cubewerk.de/list:member:regular:footer|| Am Do., 4. Juni 2026 um 16:48 Uhr schrieb Thomas Hochstein <[email protected]>: > Stefan Bauer via Mailman-users wrote: > > > Mailman logs Cannot connect to SMTP server, however the server is > > listening, but i see no connection attempts. > [...] > > If i restart the docker-core container, i see a single time the error > > "Cannot connect to SMTP server 172.17.0.1 on port 587". > > Is it possibly to connect e.g. via telnet (from the host/IP mailman is > running on, as the user mailman is running as) to the SMTP server? > That looks more like a connection problem from A to B than a mailman > problem. > > -thh > _______________________________________________ > Mailman-users mailing list -- [email protected] > To unsubscribe send an email to [email protected] > https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ > Archived at: > https://lists.mailman3.org/archives/list/[email protected]/message/XAEHMMJRQY5F4LU2HHPFXJGDELPGVRCE/ > > This message sent to [email protected] > _______________________________________________ Mailman-users mailing list -- [email protected] To unsubscribe send an email to [email protected] https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ Archived at: https://lists.mailman3.org/archives/list/[email protected]/message/RSNMV5D543GS2FB66ZHGR3KV75X35TX5/ This message sent to [email protected]
