Using gmail as relay does not work, (Cannot start TLS: handshake failure)

[malicz]

Hi and thank you for providing this well maintained docker image!

I have been using it with email service of a hosting provider, but I need to change to gmail.
This docker container is running on a server that runs many services which forward reports to this container to be send out.

error message:

2024-12-30T12:16:31.914376+01:00 INFO    postfix/smtpd[1200]: connect from docker-postfix-gw.local[172.16.43.1]
2024-12-30T12:16:31.928309+01:00 INFO    postfix/smtpd[1200]: E292446A73E: client=docker-postfix-gw.local[172.16.43.1]
2024-12-30T12:16:31.929390+01:00 INFO    postfix/cleanup[1203]: E292446A73E: message-id=<20241230111631.D7C3246A73D@dionysos>
2024-12-30T12:16:31.935274+01:00 INFO    postfix/smtpd[1200]: disconnect from docker-postfix-gw.local[172.16.43.1] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
2024-12-30T12:16:31.935334+01:00 INFO    postfix/qmgr[1199]: E292446A73E: from=<xxx>, size=459, nrcpt=1 (queue active)
2024-12-30T12:16:32.052659+01:00 INFO    postfix/smtp[1204]: SSL_connect error to smtp.gmail.com[142.250.110.108]:587: -1
2024-12-30T12:16:32.052694+01:00 WARNING postfix/smtp[1204]: warning: TLS library problem: error:0A00010B:SSL routines::wrong version number:../ssl/record/ssl3_record.c:354:
2024-12-30T12:16:32.064246+01:00 INFO    postfix/smtp[1204]: E292446A73E: to=<xxxx>, relay=smtp.gmail.com[142.250.110.108]:587, delay=0.13, delays=0.01/0.05/0.07/0, dsn=4.7.5, status=deferred (Cannot start TLS: handshake failure)

Do you have any idea what this could be?

docker-compose.yml:

services:
  postfix:
    image: boky/postfix:v4.3.0-debian
    #image: boky/postfix:v4.3.0-alpine
    container_name: postfix
    dns:
      - 192.168.xxx.xxxx
    hostname: xxxx
    environment:
      - TZ=Europe/Brussels
      - HOSTNAME=xxxx
      - POSTFIX_myhostname=xxxx
      - RELAYHOST=[smtp.gmail.com]:587
      - [email protected]
      - POSTFIX_smtp_tls_security_level=encrypt
      - XOAUTH2_CLIENT_ID=xxxx
      - XOAUTH2_SECRET=xxxx
      - XOAUTH2_INITIAL_ACCESS_TOKEN=xxxx
      - XOAUTH2_INITIAL_REFRESH_TOKEN=xxxx
      - ALLOW_EMPTY_SENDER_DOMAINS=true
      - XOAUTH2_SYSLOG_ON_FAILURE=yes
    ports:
      - 1587:587
    restart: unless-stopped
    healthcheck:
      disable: true

[malicz]

Ok, I am not sure why. But doing a full re-setup:
docker compose down
docker compose up -d
Fixed the issue?!