We are moving from an OSCommerce website to a Magento website on a different server but with the exact same domain name.
The OSCommerce site has a SHA-1 SSL cert with goDaddy which I will change to a SHA-2 cert once I Re-Key it. As far as I can see I first need to generate a new CSR from our new server and then Re-Key our SSL cert
1. What is the best process to follow when doing this so that I don't loose the SSL cert on either site/server? Should I wait until we point our domain to our new server?
2. Is it possible to test a https connection on our new Magento site before rekeying the cert?
UPDATE
Thanks for the answers, I'm concerned about not having SSL on the new site imidiatly after launch. Is there anyway I can have it immediately?
Below are the steps I believe I should take to get SSL up on the new site, can these be improved?
1 - Update DNS records to point to new Server.
2 - Generate CERTIFICATE SIGNING REQUEST (CSR) from new Server.
3 - Re-Key SSL Cert which includes uploading new CSR.
4 - Wait for new SSL Cert to be approved. How long is this normally?
5 - Download new SSL cert and place on new server.
6 - Update NGINX configuration, restart NGINX server.
7 - Turn SSL on from Magento Admin Panel.