> For the complete documentation index, see [llms.txt](https://docs.parallels.com/landing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.parallels.com/landing/ras-admin-guide/parallels-ras-21-administrators-guide/saml-sso-authentication/saml-configuration/ras-enrollment-server-high-availability.md).

# RAS Enrollment Server high availability

For high availability, multiple Enrollment Servers (ESs) can be added to each Site. All enabled and verified ESs will be used in an active/active fashion. Upon user login, requests from workload VMs such as RD Session Hosts or VDIs are equally distributed among the available ESs. In case of failures on a particular ES, the next available ES is selected and the SAML SSO authentication process continues. Specifically required for manual deployment of multiple ESs, it is important to note that all ESs in the same site share the same registration key which is required to be deployed in the specified path as mentioned in the [**RAS Enrollment Server configuration**](/landing/ras-admin-guide/parallels-ras-21-administrators-guide/saml-sso-authentication/saml-configuration/ras-enrollment-server-configuration.md) section.

{% hint style="info" %}
**Note:** Multiple ESs do not share a common certificate repository store and all certificates are segregated on each ES. This means that in case of multiple ESs, same user might have different certificates available on different ESs.
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.parallels.com/landing/ras-admin-guide/parallels-ras-21-administrators-guide/saml-sso-authentication/saml-configuration/ras-enrollment-server-high-availability.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.