Magento 2 Multi-Source Inventory: Managing Stock Across Warehouses
Understanding MSI Architecture
Magento's Multi-Source Inventory (MSI) framework, introduced in version 2.3, allows merchants to manage product stock across multiple physical locations—warehouses, stores, drop-ship vendors, and distribution centers. The system uses Sources (physical locations), Stocks (aggregations of sources assigned to sales channels), and Reservations (quantity adjustments that avoid direct database locks).
Configuration Best Practices
Define your sources to match your actual fulfillment locations, including address information that can be used for distance-based source selection. Create stocks that map to your sales channels—one stock per website if you operate multiple storefronts. Configure the Source Selection Algorithm to use either priority-based or distance-based logic depending on your fulfillment strategy. Distance-based selection minimizes shipping costs by routing orders to the nearest warehouse with available stock.
Common Implementation Challenges
The reservation system can be confusing for teams accustomed to direct stock quantity management. Reservations are created when orders are placed and cleaned up after shipment, meaning the salable quantity and physical quantity may differ. Monitor reservation inconsistencies using the built-in CLI commands and address them before they accumulate. Integration with ERP systems requires careful mapping between MSI's source codes and your ERP's warehouse identifiers.