Required DNS Records for Receiving Mail Server

1. MX Record (Essential)

Type: MX
Host: yourdomain.com
Value: mail.yourdomain.com
Priority: 10
TTL: 3600

2. A Record (Essential)

Type: A
Host: mail.yourdomain.com
Value: YOUR_SERVER_IP
TTL: 3600

3. rDNS/PTR Record (Important)

# Set this through your hosting provider/server provider
YOUR_SERVER_IP.in-addr.arpa. IN PTR mail.yourdomain.com.

4. SPF Record (Recommended)

Type: TXT
Host: yourdomain.com
Value: v=spf1 ip4:YOUR_SERVER_IP -all
TTL: 3600

Verification Commands

# Verify MX record
dig MX yourdomain.com

# Verify A record
dig A mail.yourdomain.com

# Verify PTR record
dig -x YOUR_SERVER_IP

# Verify SPF record
dig TXT yourdomain.com

Common Issues and Solutions

MX Record Issues:
- Ensure proper dot at end of domain
- Check priority number (lower = higher priority)
- Allow 24-48 hours for propagation
A Record Issues:
- Verify IP address is correct
- Ensure mail subdomain matches MX record
PTR Record Issues:
- Must match your mail server hostname
- Set through hosting provider
- Essential for preventing spam classification
Testing Mail Server Setup:

# Test SMTP connection
telnet mail.yourdomain.com 25

# Test with real email
swaks --to test@yourdomain.com --server mail.yourdomain.com