The problem is if I try to get SSL certificate from the Synology, it doesn’t work, obviously because the challenge is sent to example.com, wich reach IP-A, whereas the let’s encrypt request has been sent from IP-B.
What is the simpliest way to proceed with Synology? Generating the certificate from the VPS on IP-A and then export it to the synology? Will I have to repeat this each time the certificate will be renewed? Or another process maybe?