Healthcheck does not work when smtpd_upstream_proxy_protocol is enabled

[imro2]

Could not get the health-check to work properly after I enabled proxy protocol. Had to copy the healthcheck.sh locally, and modify the postifix check to read like this:

check_postfix() {
    printf "PROXY TCP4 192.168.2.1 1.2.3.4 12345 54321\nEHLO healthcheck\nquit\n" | \
    { while read l ; do sleep 1; echo $l; done } | \
    nc -w 2 127.0.0.1 587 | \
    grep -qE "^220.*ESMTP Postfix"
}

And add this to my compose

    volumes:
      - ./healthcheck.sh:/healthcheck.sh
    healthcheck:
      test:
        - CMD-SHELL
        - /healthcheck.sh

[bokysan]

Leaving this for reference here: https://www.postfix.org/postconf.5.html#postscreen_upstream_proxy_protocol

[imro2]

This might not be worth your time or feasible as there are more than one version of the proxy protocol. You would have to account for both or change the the health check accordingly. The other option to work around this issue is to disable health check all together.

    healthcheck:
      disable: true