On Azure App Service for WordPress, NGINX configuration changes (including rewrite rules and wildcard host handling) are made via a startup script rather than by editing NGINX config files directly.

To support WordPress Multisite with subdomains and wildcard-style behavior on this platform, the required NGINX rules must be placed into that startup script so they are applied when the App Service container starts. The startup script is the supported mechanism for updating the default NGINX configuration for WordPress on App Service.

Follow the guidance in the NGINX startup script article for WordPress on App Service to:

1. Create or update a startup script for the WordPress App Service.
2. In that script, modify the NGINX configuration to add the WordPress Multisite subdomain-related rules and any needed wildcard server_name configuration.
3. Ensure the script is configured as the App Service startup command so the NGINX changes are applied on each restart.

This approach is required because direct edits to NGINX config inside the container are not persisted and are not the supported customization method on Azure App Service.

References:

On Azure App Service for WordPress, NGINX configuration changes (including rewrite rules and wildcard host handling) are made via a startup script rather than by editing NGINX config files directly.

To support WordPress Multisite with subdomains and wildcard-style behavior on this platform, the required NGINX rules must be placed into that startup script so they are applied when the App Service container starts. The startup script is the supported mechanism for updating the default NGINX configuration for WordPress on App Service.

Follow the guidance in the NGINX startup script article for WordPress on App Service to:

1. Create or update a startup script for the WordPress App Service.
2. In that script, modify the NGINX configuration to add the WordPress Multisite subdomain-related rules and any needed wildcard server_name configuration.
3. Ensure the script is configured as the App Service startup command so the NGINX changes are applied on each restart.

This approach is required because direct edits to NGINX config inside the container are not persisted and are not the supported customization method on Azure App Service.

References: