To upload a custom SSL/TLS certificate to Fastly, you need to create a support ticket.
Make sure the certificate's private key size is 2048 bit. If possible, please provide the certificate in PEM format.
Upload the certificate and private key via SSH to a secure location on your project, and include the location in your ticket's message. Do not include the private key in the ticket itself.
If you would like the certificate to be installed at a specific date or time, include this as well and we will schedule the change for you.