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# DMARC Reporting

DMARC Reporting done via Rspamd DMARC Module.

Rspamd documentation can be found here: https://rspamd.com/doc/modules/dmarc.html

Important:

1. Change `example.com`, `mail.example.com` and `Example` to reflect your setup

2. DMARC reporting requires additional attention, especially over the first few days

3. All receiving domains hosted on mailcow send from one reporting domain. It is recommended to use the parent domain of your `MAILCOW_HOSTNAME`:

   - If your `MAILCOW_HOSTNAME` is `mail.example.com` change the following config to `domain = "example.com";`
   - Set `email` equally, e.g. `email = "noreply-dmarc@example.com";`

4. It is optional but recommended to create an email user `noreply-dmarc` in mailcow to handle bounces.

## Enable DMARC reporting

Create the file `data/conf/rspamd/local.d/dmarc.conf` and set the following content:

    reporting {
        enabled = true;
        email = 'noreply-dmarc@example.com';
        domain = 'example.com';
        org_name = 'Example';
        helo = 'rspamd';
        smtp = 'postfix';
        smtp_port = 25;
        from_name = 'Example DMARC Report';
        msgid_from = 'rspamd.mail.example.com';
        max_entries = 2k;
        keys_expire = 2d;
    }

Create or modify `docker-compose.override.yml` in the mailcow-dockerized base directory:

    version: '2.1'

    services:
      rspamd-mailcow:
        environment:
          - MASTER=${MASTER:-y}
        labels:
          ofelia.enabled: "true"
          ofelia.job-exec.rspamd_dmarc_reporting.schedule: "@every 24h"
          ofelia.job-exec.rspamd_dmarc_reporting.command: "/bin/bash -c \"[[ $${MASTER} == y ]] && /usr/bin/rspamadm dmarc_report > /var/lib/rspamd/dmarc_reports_last_log 2>&1 || exit 0\""
      ofelia-mailcow:
        depends_on:
          - rspamd-mailcow

Run `docker-compose up -d`

## Send a copy reports to yourself

To receive a hidden copy of reports generated by Rspamd you can set a `bcc_addrs` list in the `reporting` config section of `data/conf/rspamd/local.d/dmarc.conf`:

    reporting {
        enabled = true;
        email = 'noreply-dmarc@example.com';
        bcc_addrs = ["noreply-dmarc@example.com","parsedmarc@example.com"];
    [...]

Rspamd will load changes in real time, so you won't need to restart the container at this point.

This can be useful if you...

- ...want to check that your DMARC reports are sent correctly and authenticated.
- ...want to analyze your own reports to get statistics, i.e. to use with ParseDMARC or other analytic systems.

## Troubleshooting

Check when the report schedule last ran:

    docker-compose exec rspamd-mailcow date -r /var/lib/rspamd/dmarc_reports_last_log

See the latest report output:

    docker-compose exec rspamd-mailcow cat /var/lib/rspamd/dmarc_reports_last_log

Manually trigger a DMARC report:

    docker-compose exec rspamd-mailcow rspamadm dmarc_report

Validate that Rspamd has recorded data in Redis:

    docker-compose exec redis-mailcow redis-cli KEYS 'dmarc;*'
    docker-compose exec redis-mailcow redis-cli HGETALL "dmarc;example.com;20211231"

## Change DMARC reporting frequency

In the example above reports are sent once every 24 hours.

Olefia schedule has same implementation as `cron` in Go, supported syntax described at cron Documentation

To change schedule:

1. Edit `docker-compose.override.yml` and a djust `ofelia.job-exec.rspamd_dmarc_reporting.schedule: "@every 24h"` to a desired value, for example to `"@midnight"`

2. Run `docker-compose up -d`

3. Run `docker-compose restart ofelia-mailcow`

## Disable DMARC Reporting

To disable reporting:

1. Set `enabled` to `false` in `data/conf/rspamd/local.d/dmarc.conf`

2. Revert changes done in `docker-compose.override.yml` to `rspamd-mailcow` and `ofelia-mailcow`

3. Run `docker-compose up -d`

Last update: 2022-01-29 23:04:38
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