Email Infrastructure

Professional email infrastructure with Postfix and Exim expertise. Reliable delivery, spam protection, and security hardening.

Professional Email System Management

Email remains critical for business, but managing email infrastructure requires expertise. With years of Postfix and Exim experience from production environments, I build and maintain email systems that deliver reliably, fight spam effectively, and stay secure.

What I Provide

Email Server Setup

  • Postfix installation and configuration
  • Exim setup and tuning
  • SMTP relay configuration
  • Virtual domain management
  • Mailbox management
  • Alias configuration
  • SSL/TLS encryption

Email Security

  • SPF record configuration
  • DKIM signing setup
  • DMARC policy implementation
  • TLS encryption enforcement
  • Authentication mechanisms
  • Relay restrictions
  • Connection limits

Spam & Virus Protection

  • SpamAssassin integration
  • Spam filtering rules
  • Greylisting implementation
  • Blacklist/whitelist management
  • Virus scanning (ClamAV)
  • Content filtering
  • Rate limiting

Email Authentication

  • SMTP authentication
  • SASL configuration
  • User authentication
  • Certificate management
  • Secure connections
  • Password policies

High Availability

  • Multi-server setup
  • MX record configuration
  • Failover setup
  • Load balancing
  • Backup MX servers
  • Queue management
  • Disaster recovery

Monitoring & Maintenance

  • Email queue monitoring
  • Delivery tracking
  • Performance monitoring
  • Log analysis
  • Alert configuration
  • Regular maintenance
  • Backup management

Migration Services

  • Email server migration
  • Mailbox migration
  • Configuration migration
  • DNS updates
  • Testing and validation
  • Cutover planning

Who This Is For

  • Organizations Self-Hosting Email: Need expert management
  • Growing Businesses: Outgrowing basic email setups
  • Security-Conscious Companies: Want control over email infrastructure
  • Technical Teams: Need email expertise
  • Anyone Migrating: From hosted to self-hosted or vice versa

Real-World Email Experience

At DENIC eG (2015-2019), I managed:

  • Production email systems (Postfix/Exim)
  • High-volume email infrastructure
  • Email security implementation
  • Spam filtering and protection
  • Email authentication
  • Multi-server configurations
  • Disaster recovery
  • Performance optimization

Email Technologies I Work With

Mail Transfer Agents (MTA)

  • Postfix (preferred for most cases)
  • Exim (complex routing scenarios)
  • Sendmail (legacy support)

Authentication

  • SASL (Cyrus, Dovecot)
  • PAM authentication
  • LDAP integration
  • Active Directory integration

Spam Filtering

  • SpamAssassin
  • Rspamd
  • Amavis
  • Greylisting (postgrey)

Virus Scanning

  • ClamAV
  • Amavis integration

Monitoring

  • Mailgraph
  • pflogsumm (Postfix log analyzer)
  • Custom monitoring scripts

Common Email Solutions

Small Business Email Server

  • Postfix + Dovecot
  • SpamAssassin
  • SSL/TLS encryption
  • SPF/DKIM/DMARC
  • Webmail (Roundcube)
  • Backup solution

High-Volume Relay

  • Postfix configuration
  • Queue optimization
  • Connection management
  • Rate limiting
  • Performance tuning
  • Monitoring

Secure Email Gateway

  • Inbound filtering
  • Outbound scanning
  • Spam protection
  • Virus scanning
  • Content filtering
  • Compliance rules

Email Migration

  • From Exchange to Postfix
  • Between hosting providers
  • Mailbox migration
  • Configuration transfer
  • DNS updates
  • Testing phase

The Implementation Process

Phase 1: Assessment (1 week)

  • Current email analysis
  • Requirements gathering
  • Volume estimation
  • Security requirements
  • Integration needs
  • Migration planning

Phase 2: Design (1-2 weeks)

  • Architecture design
  • Security configuration
  • Spam filtering strategy
  • Authentication setup
  • High availability plan
  • Monitoring design

Phase 3: Implementation (2-4 weeks)

  • Server setup
  • Configuration
  • Security hardening
  • Testing
  • Spam filter tuning
  • Documentation

Phase 4: Migration (1-2 weeks)

  • Parallel running
  • Mailbox migration
  • DNS updates
  • Validation
  • Cutover
  • Support

Phase 5: Optimization (Ongoing)

  • Performance tuning
  • Spam filter adjustment
  • Security updates
  • Monitoring review
  • Capacity planning

Email Security Best Practices

Authentication

  • SPF: Specify authorized senders
  • DKIM: Sign outgoing messages
  • DMARC: Policy for failed authentication
  • TLS: Encrypt connections
  • SASL: Authenticate users

Protection

  • Relay restrictions
  • Connection rate limiting
  • Recipient validation
  • Greylisting
  • Spam scoring
  • Virus scanning
  • Content filtering

Monitoring

  • Queue monitoring
  • Bounce tracking
  • Authentication failures
  • Blacklist monitoring
  • Performance metrics
  • Security logs

Common Problems I Solve

  • Email Delivery Issues: SPF/DKIM/DMARC misconfigurations
  • Spam Problems: Too much spam or false positives
  • Blacklisting: IP reputation recovery
  • Performance: Slow email delivery
  • Security: Open relay or vulnerable configurations
  • Queue Buildup: Stuck messages
  • Authentication Failures: User access issues
  • Migration Issues: Mailbox transition problems

My Email Philosophy

Delivery First: Email must be delivered reliably

Security Important: Protect against spam and attacks

Authentication Essential: SPF/DKIM/DMARC are mandatory

Monitoring Critical: Know what’s happening

Performance Matters: Fast delivery is expected

Spam Balance: Block spam without false positives

What Makes This Different

Unlike basic email setups or expensive managed services:

  • Production email expertise from enterprise environments
  • Both Postfix and Exim experience
  • Security-first approach
  • Personal attention
  • Ongoing optimization

Business Benefits

Control: Full control over email infrastructure

Security: Implement policies you need

Privacy: Email stays on your servers

Customization: Configure exactly as needed

Cost: Potentially lower than hosted

Integration: Integrate with existing systems

Compliance: Meet regulatory requirements

Advanced Capabilities

Complex Routing

  • Content-based routing
  • Sender-based routing
  • Destination routing
  • Priority handling
  • Multi-path delivery

Integration

  • CRM integration
  • Ticketing system integration
  • Application email
  • Automated notifications
  • Mailing lists

Compliance

  • Email archiving
  • Retention policies
  • Encryption requirements
  • Audit trails
  • Legal hold

Monitoring & Alerting

What to Monitor:

  • Queue length
  • Delivery rates
  • Bounce rates
  • Spam scores
  • Authentication failures
  • Blacklist status
  • Disk space
  • Service availability

Alerts:

  • Queue buildup
  • Service failures
  • Blacklist additions
  • Authentication issues
  • Delivery problems
  • Disk space warnings

Email Migration Scenarios

From Hosted to Self-Hosted

  • Cost reduction
  • More control
  • Custom configuration
  • Privacy requirements

From Self-Hosted to Hosted

  • Reduce management burden
  • Better reliability
  • Compliance requirements
  • Scalability needs

Between Providers

  • Cost optimization
  • Feature requirements
  • Geographic requirements
  • Vendor change

Server Upgrade

  • New hardware
  • OS upgrade
  • Version update
  • Configuration improvements

Ongoing Maintenance

Regular Tasks

  • Security updates
  • Spam filter tuning
  • Certificate renewal
  • Backup verification
  • Log review
  • Performance monitoring
  • Blacklist checking

Periodic Tasks

  • Configuration review
  • Security audit
  • Capacity planning
  • Documentation updates
  • Policy review

Team Enablement

I don’t just set up email—I enable your team:

  • Configuration documentation
  • Troubleshooting guides
  • Common tasks training
  • Monitoring interpretation
  • Emergency procedures

Investment in Email Infrastructure

Email infrastructure requires expertise to do right. With production experience managing Postfix and Exim in enterprise environments, I ensure your email is reliable, secure, and properly configured.

This isn’t about following tutorials—it’s about applying years of email infrastructure experience to build systems that deliver reliably, fight spam effectively, and stay secure.