# xo-server-auth-saml > SAML authentication plugin for XO-Server ## Usage This plugin allows SAML users to authenticate to Xen-Orchestra. The first time a user signs in, XO will create a new XO user with the same identifier. > This plugin is based on [passport-saml](https://github.com/bergie/passport-saml), > see [its documentation](https://github.com/bergie/passport-saml#configure-strategy) > for more information about the configuration. Like all other xo-server plugins, it can be configured directly via the web interface, see [the plugin documentation](https://xen-orchestra.com/docs/plugins.html). > Important: When registering your instance to your identity provider, > you must configure its callback URL to > `http://xo.company.net/signin/saml/callback`! ## Contributions Contributions are _very_ welcomed, either on the documentation or on the code. You may: - report any [issue](https://github.com/vatesfr/xen-orchestra/issues) you've encountered; - fork and create a pull request. ## License [AGPL-3.0-or-later](https://spdx.org/licenses/AGPL-3.0-or-later) © [Vates SAS](https://vates.fr)