The Ibexa DXP excels at multi-site installations. For example, on the same installation, you can create multiple sites that share the same database, or that share the same code but use independent databases. Different sites can share the same base design and templates, but make use of site-specific overrides where relevant. For sites with user logins, you might need Single Sign-On (SSO) behavior, so that whenever a user logs in to one site, they are automatically logged in to all sites without having to re-enter their credentials. In this post, we'll review how to implement SSO logins on an Ibexa DXP website, specifically one where some of the sites are still using eZ Publish legacy siteaccesses.