Command '['postfix', 'start']' returned non-zero exit status 1

[IndependentCreator]

I've successfully used the mdomke/concourse-email-resource docker image in the past, but since yesterday when I set up a new concourse server, concourse is reporting a fatal error from the resource:

Using dir /tmp/build/put
Logging payload to /tmp/tmpxxlhbrfy
Command '['postfix', 'start']' returned non-zero exit status 1.

Here is my test pipeline:

$ cat email_test.yml
---
resource_types:
  # See https://github.com/mdomke/concourse-email-resource
  - name: email
    type: docker-image
    source:
      repository: mdomke/concourse-email-resource
resources:
  - name: send-email
    type: email
    source:
      from: [email protected]
jobs:
- name: email-job
  plan:
  - put: send-email
    params:
      to:
        - [email protected]
      subject_text: Email from concourse
      body_text: Email body

Here's what I get when I run postfix start manually within the container:

fly -t test intercept sh -j email_test/email-job -b18
/tmp/build/put # cat /etc/issue
Welcome to Alpine Linux 3.4
Kernel \r on an \m (\l)

/tmp/build/put # postfix start
postfix: warning: smtputf8_enable is true, but EAI support is not compiled in
postsuper: warning: smtputf8_enable is true, but EAI support is not compiled in
postsuper: fatal: scan_dir_push: open directory defer: Permission denied
postfix/postlog: warning: smtputf8_enable is true, but EAI support is not compiled in
postfix/postfix-script: fatal: Postfix integrity check failed!

Any ideas about what might be going on here?

[IndependentCreator]

I was able to get things working by downgrading concourse to version 3.0.1, but I'm not sure what the root cause is. Based on the release notes for version 3.1.0, I thought maybe it had something to do with the privileged user changes in that release: https://concourse.ci/downloads.html#v3.1.0

However, adding privileged: true to my resource_type configuration didn't fix things for me when running 3.1.x

[mdomke]

Hmm… We are running on concourse 3.3.2. I'm actually not seeing any error message on our site when sending e-mails but we also didn't receive mails for failing builds. I'll try to look into this…

[IndependentCreator]

Thanks for your response. I should add that concourse 3.3.2 also gives me this error.