# Authorities Authorities contain public SSH keys or public SSH certificate authorities. Each authority can contain one public SSH key or certificate authority. The authorities are applied to instances at each boot only if the instance is stop and started again from the web console. Restarting the instance from the system will not update the cloud-init configuration. Authorities are selected by matching instances in the same organization that have matching roles. The SSH username will always be cloud for the Pritunl Cloud provided images. ### SSH Certificates SSH certificate authorities can be configured by adding the certificate and entering principals. The principals field allows controlling what certificate authority principals will have access to the server. --- # Agent Instructions: 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: ``` GET https://docs.pritunl.com/kb/cloud/components/authorities.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.