I use a product software by Manage Engine called Key Manager Plus to create and request new certificates on Let's Encrypt. Creating a standard ssl certificates works fine. But when I tried requesting a new ssl certificates with added SAN information, it just failed.
The added SAN information included is in public IP format. Do Let's Encrypt allow creating new certificates having public IPs including in the SAN?
Correct, unfortunately. It was more work than first anticipated.
@cuy ZeroSSL issues publicly trusted certs for IP addresses, but only using their webpanel and not when using ACME, which has a few drawbacks of its own (only 3 free certs, no SAN et cetera).