Email Migration Guide

Migrate email data from your existing mail server to your new email hosting.

How It Works

1. You provide SSH access to your source mail server
2. The system connects and syncs your maildir folders
3. Emails are imported into your new mailboxes
4. You can close your browser - migrations continue in the background
5. You'll be notified when each mailbox completes

Before You Start

For faster migrations, optimize your source server for concurrent SSH connections.

Increase SSH Connection Limits

Edit /etc/ssh/sshd_config on your source server:

MaxStartups 50:30:100

Then restart SSH:

systemctl restart sshd

Increase File Descriptor Limits

Edit /etc/security/limits.conf:

* soft nofile 65535
* hard nofile 65535

Apply immediately (or re-login):

ulimit -n 65535

Verify Settings

ulimit -n                        # Should show: 65535
sshd -T | grep maxstartups       # Should show: maxstartups 50:30:100

Starting a Migration

1. Go to Apps > Email > Migrations > New Migration
2. Enter your source server details:
   • Host - IP address or hostname of your current mail server
   • SSH User - Usually root
   • Maildir Path - Where mailboxes are stored (e.g., /home/mail/yourdomain.com)
3. Select the target domain in your account
4. Click Discover Mailboxes to scan the source server
5. Select which mailboxes to migrate
6. Click Start Migration

During Migration

• Up to 6 mailboxes are migrated simultaneously
• Smaller mailboxes complete first
• Progress updates in real-time
• You can safely close your browser - migrations continue on the server
• You'll receive notifications when jobs complete

Time Estimates

Times assume good network conditions. Actual times vary based on network speed and server load.

Troubleshooting

Connection Refused

If discovery or migration fails with "Connection refused":

1. Verify SSH is running on the source server
2. Check the MaxStartups setting (see above)
3. Ensure the IP/hostname is correct
4. Check firewall allows SSH connections

Migration Stuck or Slow

For very large mailboxes:

1. Check network connectivity between servers
2. Large mailboxes (10GB+) may take longer - this is normal
3. The system automatically handles timeouts and retries

Mailbox Not Found

If a source mailbox shows "No match":

1. Create the corresponding mailbox in your account first
2. Mailbox names must match exactly (case-insensitive)
3. Re-run discovery after creating missing mailboxes

Resume Failed Migrations

If a migration was interrupted:

1. Simply restart the migration from the UI
2. The system automatically resumes from where it left off
3. Only new or changed emails are transferred