Moving Sites In and Out WordPress Multisite with All-in-One WP Migration

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  • / Author: Yani I

WordPress Multisite is powerful, but what happens when you need to break free a subsite to its own installation? Or perhaps you want to consolidate a standalone site into your existing multisite network?

This comprehensive guide covers both scenarios using All-in-One WP Migration, walking you through the unique challenges and solutions for multisite migrations in both directions.

Table of Contents

Understanding WordPress Multisite Architecture

Before diving into migrations, it’s crucial to understand what makes multisite different:

Database Structure

In a multisite network:

  • The main site uses standard WordPress tables (wp_posts, wp_options, etc.)
  • Each subsite gets its own set of tables with unique prefixes (wp_2_posts, wp_3_posts, etc.)
  • Some tables are shared across the network (wp_users, wp_usermeta)
  • Media files are organized differently in wp-content/uploads/sites/[site-id]/

This architecture creates unique challenges when migrating sites in or out of the network.

PART 1

Exporting a Subsite from Multisite to Standalone

When You Need This

  • A client’s subsite has outgrown the network
  • You need independent hosting for performance reasons
  • The subsite requires plugins incompatible with multisite
  • Separate billing or management is required

Prerequisites

Before starting, ensure you have:

  • Administrator access to both the multisite network and the destination server
  • All-in-One WP Migration installed network-wide
  • A fresh WordPress installation at the destination
  • FTP/SSH access to both servers (for troubleshooting)

Step-by-Step Export Process

1

Prepare the Subsite

First, clean up your subsite to ensure a smooth migration:

1. Deactivate Network-Only Plugins

  • Visit the subsite’s Plugins page
  • Note which plugins are “Network Activated” – you’ll need to install these separately
  • Take screenshots of active plugins for reference

2. Document Custom Configurations

  • Check for any mu-plugins (must-use plugins)
  • Note any custom constants in wp-config.php
  • Document any server-specific configurations

3. Update URLs if Needed

  • If the subsite uses a subdomain (site.network.com), ensure DNS is ready
  • For subdirectory sites (/site/), prepare for the URL structure change
2

Export with All-in-One WP Migration

1. Navigate to the Subsite

  • In Network Admin, go to Sites
  • Click “Visit” under your target subsite
  • Go to All-in-One WP Migration → Export

2. Configure Export Settings

Advanced Options:
✓ Do not export database (UNCHECK - you need the database!)
✓ Do not export media library (UNCHECK if you need media)
✗ Do not replace email domain (usually keep unchecked)

3. Handle Multisite-Specific Options

  • The plugin automatically detects multisite
  • It will export only the current subsite’s data
  • Shared user data is intelligently handled

4. Export to File

  • Choose “Export to File”
  • Save the .wpress file locally
  • Note the file size for upload limits
3

Prepare the Destination Site

1. Install Fresh WordPress

  • Use the same WordPress version as your multisite
  • Don’t run the famous 5-minute install yet

2. Install All-in-One WP Migration

  • Upload and activate the plugin

3. Match PHP Version

  • Ensure PHP versions match between source and destination
  • Check for required PHP extensions
4

Import to Standalone Site

1. Begin Import Process

  • Go to All-in-One WP Migration → Import
  • Upload your .wpress file
  • Click “Proceed” when prompted

2. Handle the Transformation

The plugin automatically:

  • Converts multisite tables to single-site format
  • Adjusts table prefixes (wp_2_ becomes wp_)
  • Maps user roles correctly

3. Post-Import Tasks

  • Log in with your subsite administrator credentials
  • Visit Settings → Permalinks and re-save
  • Install previously network-activated plugins
  • Update any hardcoded multisite paths

Common Issues When Exporting from Multisite

Issue 1: Missing Media Files
Problem: Media uploaded to other subsites isn’t included
Solution: Media files are segregated by site ID. Only media in /uploads/sites/[your-site-id]/ is exported

Issue 2: Broken User Permissions
Problem: Users can’t log in or have wrong capabilities
Solution: The plugin handles user migration, but you may need to:

  • Reset user passwords
  • Manually adjust user roles
  • Re-assign content to users

Issue 3: Network-Activated Plugins Missing
Problem: Some functionality is missing after migration
Solution: Document network-activated plugins before migration and install them individually on the standalone site

PART 2

Importing a Standalone Site into Multisite

When You Need This

  • Consolidating multiple sites under one network
  • Centralizing site management
  • Sharing users across multiple sites
  • Reducing hosting costs

Prerequisites

  • An existing multisite network
  • Network Admin access
  • All-in-One WP Migration installed network-wide
  • Understanding of your network’s structure (subdomain vs subdirectory)

Step-by-Step Import Process

1

Prepare the Standalone Site

1. Audit the Site

  • Check for multisite-incompatible plugins
  • Review custom code for hardcoded URLs
  • Document all active plugins and themes

2. Clean Up the Database

Recommended cleanups:
- Remove spam comments
- Delete post revisions
- Clean up transients
- Optimize database tables

3. Export the Standalone Site

  • Use All-in-One WP Migration → Export
  • Include all content (don’t exclude anything)
  • Download the .wpress file
2

Create a New Subsite

1. Add New Site in Network Admin

Network Admin → Sites → Add New
- Site Address: choose carefully (can't be changed easily)
- Site Title: can be changed later
- Admin Email: use a valid email

2. Configure the Subsite

  • Visit the new empty subsite
  • Activate All-in-One WP Migration
  • Ensure it’s ready for import
3

Import into the Subsite

1. Navigate to the New Subsite

  • Don’t use Network Admin for this
  • Go directly to the subsite’s dashboard
  • All-in-One WP Migration → Import

2. Upload and Import

  • Select your .wpress file
  • The plugin will warn about overwriting
  • Proceed with the import

3. Multisite Conversion Magic

The plugin automatically:

  • Converts single-site tables to multisite format
  • Adjusts table prefixes (wp_ becomes wp_[site-id]_)
  • Integrates with shared user tables
  • Relocates media to /uploads/sites/[site-id]/

4

Post-Import Adjustments

1. User Integration

  • Existing users are mapped to network users
  • New users are added to the network
  • User roles are adjusted for multisite context

2. Plugin Compatibility

  • Deactivate incompatible plugins
  • Some plugins may need network activation
  • Check for multisite-specific settings

3. URL Structure

  • Subdomain: Ensure DNS points correctly
  • Subdirectory: URL structure changes automatically
  • Update any hardcoded URLs in content

Advanced Considerations for Importing

Handling Domain Mapping

If your standalone site uses a custom domain:

1. Before Import

  • Set up domain mapping plugin on the network
  • Configure DNS to point to multisite server

2. After Import

  • Map the domain to the new subsite
  • Test thoroughly before switching DNS

Managing Plugin Conflicts

Some plugins don’t play well with multisite:

Common problematic plugins:
- Caching plugins (need multisite-compatible versions)
- Security plugins (may conflict with network-wide security)
- Backup plugins (might backup entire network)
- SEO plugins (check for multisite support)

Database Prefix Conflicts

If importing multiple sites:

  • Ensure unique site IDs
  • Check for table prefix conflicts
  • Monitor database size growth

Best Practices for Both Directions

1. Always Test First

  • Use a staging environment
  • Test with a copy of your production data
  • Verify all functionality before going live

2. Maintain Backup Strategies

Recommended backup approach:
- Full network backup before adding/removing sites
- Individual subsite backups
- Database snapshots at each major step

3. Document Everything

Keep records of:

  • Original URLs and new URLs
  • Plugin configurations
  • Custom code modifications
  • User permission changes

4. Handle Media Carefully

  • Understand media file organization differences
  • Check for broken image links
  • Regenerate thumbnails if needed

5. Plan for SEO Impact

  • Set up proper redirects
  • Update Google Search Console
  • Monitor 404 errors
  • Maintain URL structure when possible

Troubleshooting Common Issues

Export Issues

“File too large” errors
  • Split the migration using partial exports
  • Increase server limits
  • Use alternative transfer methods (FTP, SSH)

“Missing tables” warnings
  • Verify All-in-One WP Migration version
  • Check database permissions
  • Ensure complete export

Import Issues

“Cannot create database tables”
  • Check database user permissions
  • Verify table prefix availability
  • Look for existing tables with same prefix

“Users cannot log in”
  • Reset passwords
  • Check user role mappings
  • Verify cookie domain settings

Post-Migration Issues

Broken layouts or missing styles
  • Clear all caches
  • Check theme compatibility
  • Regenerate CSS files
  • Verify asset URLs

Plugin functionality broken
  • Check for multisite compatibility
  • Review error logs
  • Test plugin activation order

Performance Considerations

Large Site Migrations

For sites over 1GB:

  • Consider using Pro version for better performance
  • Migrate during low-traffic hours
  • Use incremental migrations if available
  • Monitor server resources

Database Optimization

After migration:

-- Optimize all tables
OPTIMIZE TABLE `wp_posts`, `wp_postmeta`, `wp_options`;

-- Check for orphaned data
SELECT * FROM wp_postmeta WHERE post_id NOT IN (SELECT ID FROM wp_posts);

Security Considerations

During Migration

  • Use secure transfer methods
  • Encrypt backup files
  • Limit access to migration tools
  • Monitor for unauthorized access

After Migration

  • Update all passwords
  • Review user permissions
  • Check file permissions
  • Update security plugins

Conclusion

Migrating WordPress sites in and out of multisite networks doesn’t have to be daunting. All-in-One WP Migration handles the complex database transformations and file reorganizations automatically, making what was once a manual, error-prone process into a streamlined workflow.

Key takeaways:

  • Exporting from multisite: The plugin intelligently extracts just your subsite’s data
  • Importing to multisite: Automatic conversion handles table prefixes and user integration
  • Planning is crucial: Understanding the differences between single and multisite architectures helps avoid issues
  • Test everything: Always use a staging environment first

Whether you’re breaking free from a network or consolidating sites, these migration patterns will serve you well. The tools have evolved to make these complex migrations accessible, but understanding what’s happening under the hood ensures success.

Remember: every migration is unique. Use this guide as your foundation, but always be prepared to adapt to your specific situation. Happy migrating!