STARLIGHT™ MAIL BRIDGE

Mail Bridge is an outbound VPS email service, available as an add-on for Starlight Virtual Machines. It safely opens SMTP port 25 so you can run Mail Transfer Agents (Postfix, Exim, etc) for your applications to send trusted, reliable email directly from your server.

Most cloud providers block port 25 by default to prevent spam. Mail Bridge unlocks port 25 the safe way: with an isolated Virtual Machine IP, abuse protection, and proper DNS identity.

Mail Bridge helps you handle business emails for VPS. It's ideal for sending:

• Transactional emails (password resets, receipts, notifications)
• System alerts and cron reports
• Application-generated emails (SaaS, CMS, e-commerce)
• Custom mail server setups (Postfix, Exim, etc.)

Mail Bridge uses following traffic policies:

Internal inbound (your VM → Mail Bridge): To ensure efficient processing, connections on Port 25 must be plaintext only.

• STARTTLS is not offered or accepted
• Any connection attempting TLS/SSL or STARTTLS is rejected and the message is not accepted for relay

External outbound (Mail Bridge → Internet): We prioritize security for final delivery. Mail Bridge acts as a standard SMTP client using Opportunistic TLS.

• If STARTTLS is not available, the message is delivered in plaintext

This matches typical outbound SMTP behavior and ensures broad compatibility with receiving servers.

To use Mail Bridge, you must configure your own Message Transfer Agent (MTA) on the VM, such as Postfix, Exim, or Sendmail. Mail Bridge does not provide an MTA or inbox hosting; it only enables outbound delivery through a Virtual Machine IP.

During initial setup, you must also:

• Provide a domain name for the PTR (reverse DNS) of the Virtual Machine IP.
• Use a dedicated subdomain such as mailout.example.com for the PTR.
• Create and maintain an A record for that hostname pointing back to the same Virtual Machine IP (forward-confirmed rDNS).
• Configure your MTA's HELO/EHLO to use that hostname for best deliverability.
• Publish an SPF record for any domain you send mail from.

These requirements help establish proper mail identity, improve reputation, and ensure your MTA can relay outbound email through Mail Bridge correctly. Also, ensure your messages' format complies with RFC standards.

Yes. You can run your own MTA (Postfix, Exim, etc.) and send outbound email directly from your VM, using your isolated Virtual Machine IP.

IP reputation depends on multiple elements, including:

• Your email content and sending behavior
• Your configuration (SPF, DKIM, DMARC, bounce handling)
• The accuracy of automated scanning systems
• The historical activity of the IP before you received it
• External third-party blocklist policies (which Spaceship cannot control)

Mail Bridge may not be used to send executables or malware, malformed or forged email headers, or unsolicited bulk or commercial email (spam). These behaviors negatively impact sender reputation and may harm the platform. To protect overall platform reputation, we may take action if a Virtual Machine IP or domain becomes blocklisted, or if complaint, bounce, or abuse signals exceed acceptable levels.

Please note that remediation of domain/IP reputation issues is the customer's responsibility, as these are caused by factors under the customer's control.

Mail Bridge is available as a prepaid add-on:

• 1 month: $5
• 3 months: $15
• 1 year: $60