Magento 2 MSI (Multi-Source Inventory) Explained
What is Magento 2 MSI?
MSI (Multi-Source Inventory) in Magento 2 is an advanced inventory management system introduced in Magento 2.3. It allows merchants to manage inventory across multiple physical locations such as warehouses, stores, and suppliers.
Unlike the default single-stock system, MSI enables better stock control, scalability, and flexibility by supporting multiple inventory sources and mapping them to different sales channels (websites).
Main Purpose of MSI
- Manage inventory across multiple warehouses.
- Prevent overselling using reservations.
- Improve order fulfillment efficiency.
- Support multi-website inventory management.
- Enable advanced shipping logic.
- Provide scalability for enterprise stores.
Key Features
| Feature | Description |
|---|---|
| Multiple Sources | Manage inventory across different warehouses or locations. |
| Stocks | Virtual grouping of sources assigned to sales channels. |
| Reservations | Temporarily reserve stock when an order is placed. |
| Source Selection Algorithm (SSA) | Automatically selects the best source for shipment. |
| Salable Quantity | Available quantity after considering reservations. |
| Backorders Support | Allows customers to place orders even when stock is low. |
How Magento MSI Works
Magento MSI follows this process:
- Customer places an order.
- System creates a reservation for the ordered quantity.
- Source Selection Algorithm decides the shipping source.
- Shipment is created from the selected source.
- Inventory is deducted after shipment.
This approach ensures accurate stock management and prevents overselling in high-traffic eCommerce stores.
Magento MSI Architecture
- Sources – Physical inventory locations.
- Stocks – Virtual grouping of sources.
- Source Items – Product quantity per source.
- Reservations – Temporary stock holds.
- SSA (Algorithm) – Decides shipping source.
Example CLI Commands for MSI
Important Database Tables
- inventory_source
- inventory_stock
- inventory_source_item
- inventory_reservation
Common Issues in Magento MSI
- Product showing out of stock despite quantity available
- Reservation mismatch issues
- Incorrect salable quantity
- Indexer not updating stock status
- Issues in multi-website stock mapping
Fix for Common MSI Issues
Benefits of Using Magento MSI
- Improves inventory accuracy.
- Supports multi-warehouse systems.
- Prevents overselling.
- Enhances order fulfillment.
- Scalable for enterprise-level stores.
Real-World Use Case
An eCommerce store with warehouses in Delhi and Mumbai can use MSI to manage stock separately at both locations. When a customer places an order, Magento automatically selects the nearest or highest-priority warehouse for shipping.
Conclusion
Magento 2 MSI is a powerful inventory management system designed for modern eCommerce needs. It allows businesses to efficiently manage stock across multiple locations, improve order fulfillment, and scale operations seamlessly. Understanding MSI is essential for Magento developers and is frequently asked in Adobe Commerce certification exams.