The certificate is used to authenticate VMM servers with Azure Site Recovery. You'll need to upload the certificate (.cer) ...

The certificate is used to authenticate  VMM servers with Azure Site Recovery. You'll need to upload the certificate (.cer)  to the vault. Use a valid SSL certificate that complies with vault requirements. The vault key ensures the integrity of vault operations. Generate a vault key. You'll need to copy and paste this key in when you install the Provider on a VMM server to register it in the vault.