Custom SMTP

E-Mails generated from the app are sent by by default. Customers on some plans can use a custom SMTP server for all outbound mail, allowing full control over the from address, and integration with email security and authentication standards such as DKIM and SPF. supports any type of custom mail server that supports the SMTP standard, which is nearly anything that supports sending mail.

SMTP Settings

The Custom SMTP feature supports the following settings

  • Server address The fully qualified hostname of the SMTP server.
  • Server port The number of the port you connect to for SMTP. This often port 25 for unencrypted traffic.
  • Authentication type How you authenticate to the SMTP service. Valid options are none, plain, normal, or cram_md5. Your mail provider should tell you which option is appropriate for your service.
  • SMTP username The username used to log into your SMTP server
  • SMTP password The password used to log into your SMTP server.
  • From address. The email address that messages will be sent from.
  • Email notifications reply-to address The email address used for replies to emails sent from (Optional)

Viewing and Configuring SMTP Settings with the Web UI

To set the custom SMTP settings, log in to the web UI as a site admin and access the SMTP settings from Settings > Site Identity > Custom SMTP. By default, the setting will be "Use standard outbound SMTP server", which uses the email service. Changing the setting to "Use custom outbound SMTP server" will display the SMTP settings detailed above.

SMTP Settings and the API

You can use the Sites API to show or change your site settings.

Command Line Application (CLI)

Use the command line application (CLI) to view your current site settings with this command:

files-cli sites get --fields smtp_address,smtp_port,smtp_authentication,smtp_username,smtp_from

To change any of the settings, use this command (replace things like $SMTP_SERVER with the real values)

files.cli sites update --smtp-address $SMTP_ADDRESS --smtp-port $SMTP_PORT \
--smtp-authentication $SMTP_AUTH --smtp-username $SMTP_USERNAME \
--smtp-password $SMTP_PASSWORD --smtp-from $SMTP_FROM --reply-to-email $REPLY_TO

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