Multi-site Configuration

Multi-site Configuration lets Drupal sites sharing a database and active configuration storage use site-specific settings while retaining a common configuration baseline.

For example, sites can share most of their configuration while using different site names or other settings. Each site is identified by a key defined in its settings.php file.

Features

• Read common configuration with site-specific overrides.
• Save configuration under a prefix unique to each site.
• Initialize new site-specific configuration from the effective common values.
• Separate cache bins by site key when accessed through the decorated cache factories.

How it works

Define a unique multisite_config_key in each site's settings.php. The module uses this key to store and retrieve site-specific configuration. Sites without a key continue to read and modify the common configuration directly.

Scope

This module is intended for related sites that deliberately share configuration storage. It does not configure multisite routing or database connections, and it does not isolate content, users, sessions, or files. It is not a security boundary between independent tenants.

Configuration export/import workflows and compatibility with other modules that replace or decorate the configuration and cache factories should be validated for your installation.