The Platform Services Controller handles the authentication between Site Recovery Manager and vCenter Server at the vCenter Single Sign-On level.
All communications between Site Recovery Manager and vCenter Server instances take place over transport layer security (TLS) connections. Previous versions of Site Recovery Manager supported both secure sockets layer (SSL) and TLS connections. This version of Site Recovery Manager only supports TLS, due to weaknesses identified in SSL 3.0.
Solution User Authentication
Site Recovery Manager 8.x uses solution user authentication to establish secure communication to remote services, such as the Platform Services Controller and vCenter Server. A solution user is a security principal that the Site Recovery Manager installer generates. The installer assigns a private key and a certificate to the solution user and registers it with the vCenter Single Sign-On service. The solution user is tied to a specific Site Recovery Manager instance. You cannot access the solution user private key or certificate. You cannot replace the solution user certificate with a custom certificate.
After installation, you can see the Site Recovery Manager solution user in the Administration view of the vSphere Web Client. Do not attempt to manipulate the Site Recovery Manager solution user. The solution user is for internal use by Site Recovery Manager, vCenter Server, and vCenter Single Sign-On.
During operation, Site Recovery Manager establishes authenticated communication channels to remote services by using certificate-based authentication to acquire a holder-of-key SAML token from vCenter Single Sign-On. Site Recovery Manager sends this token in a cryptographically signed request to the remote service. The remote service validates the token and establishes the identity of the solution user.
Solution Users and Site Recovery Manager Site Pairing
When you pair Site Recovery Manager instances across vCenter Single Sign-On sites that do not use Enhanced Linked Mode, Site Recovery Manager creates an additional solution user for the remote site at each site. This solution user for the remote site allows the Site Recovery Manager Server at the remote site to authenticate to services on the local site.
When you pair Site Recovery Manager instances in a vCenter Single Sign-On environment with Enhanced Linked Mode, Site Recovery Manager at the remote site uses the same solution user to authenticate to services on the local site.
Site Recovery Manager SSL/TLS Server Endpoint Certificates
Site Recovery Manager requires an SSL/TLS certificate for use as the endpoint certificate for all TLS connections established to Site Recovery Manager. The Site Recovery Manager server endpoint certificate is separate and distinct from the certificate that is generated during the creation and registration of a Site Recovery Manager solution user.
For information about the Site Recovery Manager SSL/TLS endpoint certificate, see Creating SSL/TLS Server Endpoint Certificates for Site Recovery Manager in the Site Recovery Manager Installation and Configuration guide.