Building Your Own Email Infrastructure: A Complete Guide

Building your own email infrastructure gives you complete control over deliverability, costs, and data privacy. Here's everything you need to know.

Why Build Your Own Infrastructure?

Benefits

Cost Savings at Scale At high volumes (1M+ emails/month), self-hosted infrastructure can reduce costs by 60-80%.

Data Control Your data stays on your servers. No third-party access, full compliance control.

Deliverability Control Build and maintain your own sender reputation without being affected by other senders.

Customization Configure everything exactly how you need it for your use case.

Challenges

• Requires technical expertise
• Ongoing maintenance and monitoring
• Initial setup time investment
• Need to handle compliance yourself

The Infrastructure Stack

Mail Transfer Agent (MTA)

Popular options include:

• Postfix: Most widely used, excellent documentation
• Sendmail: Original MTA, complex configuration
• PowerMTA: Commercial option with advanced features

Mail Server Setup

Key components:

1. Dedicated server or cloud instance
2. Multiple IPs for sending
3. Reverse DNS configuration
4. SSL certificates

Step-by-Step Setup Process

Step 1: Server Provisioning

Choose a provider that allows email sending:

• Vultr
• OVH
• Hetzner

Avoid AWS and Google Cloud for primary sending—their IPs often have poor reputation.

Step 2: DNS Configuration

Set up these records:

# SPF Record
v=spf1 ip4:YOUR_IP -all

# DKIM Record
mail._domainkey IN TXT "v=DKIM1; k=rsa; p=YOUR_PUBLIC_KEY"

# DMARC Record
_dmarc IN TXT "v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com"

Step 3: Install and Configure Postfix

Basic Postfix configuration for high-volume sending:

# /etc/postfix/main.cf
myhostname = mail.yourdomain.com
mydomain = yourdomain.com
inet_interfaces = all
smtp_tls_security_level = may
smtp_tls_note_starttls_offer = yes

Step 4: IP Warm-up

Critical for new infrastructure:

| Week | Daily Volume | Target Domains | |------|-------------|----------------| | 1 | 50-100 | Your most engaged | | 2 | 200-500 | Engaged segment | | 3 | 1,000-2,000 | Broader audience | | 4 | 5,000-10,000 | General list | | 5+ | Full volume | All subscribers |

Step 5: Monitoring Setup

Essential monitoring tools:

• Postfix logs: Track delivery status
• Bounce handling: Process bounces immediately
• Blacklist monitoring: Check daily
• Deliverability testing: Regular inbox placement tests

Best Practices

Use Multiple IPs

Separate IPs for:

• Marketing emails
• Transactional emails
• Re-engagement campaigns

Implement Feedback Loops

Register for feedback loops with major ISPs:

• Gmail Postmaster Tools
• Microsoft SNDS
• Yahoo Complaint Feedback Loop

Handle Bounces Properly

• Hard bounces: Remove immediately
• Soft bounces: Retry 3 times, then remove
• Complaints: Remove immediately

When to Get Help

Building email infrastructure is complex. Consider professional help if:

• You're sending 1M+ emails monthly
• Deliverability is critical to revenue
• You lack in-house expertise
• You need to meet compliance requirements

Our infrastructure consultancy service provides hands-on guidance through every step.

Conclusion

Self-hosted email infrastructure offers significant advantages for organizations with the resources to build and maintain it. Whether you go DIY or get expert help, the investment in owning your email delivery pays dividends in control, cost savings, and deliverability.