How to Setup Email Archiving Server with Postfix on Ubuntu 22.04

Introduction

Email archiving means keeping a copy of all incoming and outgoing emails in a safe place.
In production environments, companies must store emails for security, legal compliance, and backup.
With Postfix on Ubuntu 22.04, we can set up an email archiving server so no email is ever lost.

Concept of Email Archiving

Postfix allows us to make a copy of every email using the always_bcc or recipient_bcc_maps parameter.
This ensures that whenever a user sends or receives an email, a copy is delivered to a special archive mailbox.

Step 1: Prerequisites

• Ubuntu 22.04 server with Postfix installed
• A working mail domain (example: bitscentric.local)
• Admin user with sudo access

Step 2: Update System

sudo apt update -y && sudo apt upgrade -y

Step 3: Install Postfix (if not installed)

sudo apt install postfix mailutils -y

Choose “Internet Site” when asked during installation.
Set system mail name as bitscentric.local.

Step 4: Create Archive Mailbox

We will create a mailbox called archive@bitscentric.local to store all email copies.

sudo adduser archive

Set a strong password for this account. This user will collect all archived emails.

Step 5: Configure Postfix for Archiving

Edit Postfix main configuration file:

sudo nano /etc/postfix/main.cf

Add the following line at the bottom:

always_bcc = archive@bitscentric.local

This will send a copy of every incoming and outgoing email to archive@bitscentric.local.

Step 6: Restart Postfix

sudo systemctl restart postfix

Step 7: Test Archiving

Send an email from any user in your domain:

echo "Test Archive" | mail -s "Archive Test" user@bitscentric.local

Now check the archive mailbox:

mail -u archive

You should see a copy of the test mail.

Step 8: Storing Archive Mails Safely

For production use, you should store archived mails safely:

• Use Dovecot IMAP to allow secure access to archive@bitscentric.local.
• Set up a backup system (rsync, Borg, Restic) to copy /var/mail/archive regularly.
• Use a dedicated storage server for archiving if mail volume is high.

Advanced Option: Archive Specific Domains or Users

Instead of archiving all emails, you can configure per-user or per-domain archiving.

Create a BCC map file:

sudo nano /etc/postfix/recipient_bcc

Add rules:

@bitscentric.local   archive@bitscentric.local
ceo@bitscentric.local   legalarchive@bitscentric.local

Convert into database format:

sudo postmap /etc/postfix/recipient_bcc

Edit /etc/postfix/main.cf and add:

recipient_bcc_maps = hash:/etc/postfix/recipient_bcc

Restart Postfix:

sudo systemctl restart postfix

Step 9: Security Best Practices

• Restrict access to archive mailbox (only administrators should access).
• Use encryption (TLS/SSL) for archiving server.
• Implement retention policies (e.g., keep emails for 5 years).
• Regularly backup the archive mailbox.
• Monitor mail logs (/var/log/mail.log) to confirm archiving works.

Conclusion

Email archiving is critical for production mail systems.
By using Postfix on Ubuntu 22.04, we can easily set up an archiving server where all user mails are copied for security and compliance.
With best practices like secure access, backups, and retention policies, your company can protect important communication and meet industry standards.