# Adjusting mxisd Identity Server configuration (optional)
By default, this playbook configures an [mxisd](https://github.com/kamax-io/mxisd) Identity Server for you.
This server is private by default, potentially at the expense of user discoverability.
## Matrix.org lookup forwarding
To ensure maximum discovery, you can make your identity server also forward lookups to the central matrix.org Identity server (at the cost of potentially leaking all your contacts information).
Enabling this is discouraged and you'd better [learn more](https://github.com/kamax-io/mxisd/blob/master/docs/features/identity.md#lookups) before proceeding.
Enabling matrix.org forwarding can happen with the following configuration:
To use the [Registration](https://github.com/kamax-matrix/mxisd/blob/master/docs/features/registration.md) feature of mxisd, you can make use of the following variables:
-`matrix_synapse_enable_registration` - to enable user-initiated registration in Synapse
-`matrix_synapse_registrations_require_3pid` - to control the types of 3pid (`'email'`, `'msisdn'`) required by the Synapse server for registering
- variables prefixed with `matrix_nginx_proxy_proxy_matrix_3pid_registration_` (e.g. `matrix_nginx_proxy_proxy_matrix_3pid_registration_enabled`) - to configure the integrated nginx webserver to send registration requests to mxisd (instead of Synapse), so it can apply its additional functionality
-`matrix_mxisd_configuration_extension_yaml` - to configure mxisd as required. See the [Registration feature's docs](https://github.com/kamax-matrix/mxisd/blob/master/docs/features/registration.md) for inspiration. Also see the [Additional features](#additional-features) section below to learn more about how to use `matrix_mxisd_configuration_extension_yaml`.
What this playbook configures for your is some bare minimum Identity Server functionality, so that you won't need to rely on external 3rd party services.
To learn more about how to do this, refer to the information about `matrix_mxisd_configuration_extension_yaml` in the [default variables file](../roles/matrix-mxisd/defaults/main.yml) of the mxisd component.
If email address validation emails sent by mxisd are not reaching you, you should look into [Adjusting email-sending settings](configuring-playbook-email.md).