How to enable/disable DKIM signing for all domains in Plesk for Linux

Question

How to enable/disable DKIM signing for all domains in Plesk for Linux?

Answer

1. Connect to a Plesk server via SSH.

2. Allow signing outgoing mail by DKIM spam protection on a server level:

   # plesk bin mailserver --sign-outgoing-mail true

3. Run the following command to enable DKIM signing for all domains:

   # for domain in $(plesk db -Ne 'SELECT name FROM domains WHERE parentDomainId=0;'); do plesk bin domain_pref --update $domain -sign_outgoing_mail true; done

   Note: To disable DKIM signing for all domains, switch the value to from true to false.

Additional Information

To learn more about mail protection, see this KB article.