Is it possible to make ssl letsencrypt for subdomains?

Question

Digital certificates

The domain already has a paid ssl certificate.
But there are also subdomains - like novosibirsk.site.ru, moscow.site.ru
Is it possible to make free SSL certificates from letsencypt for them? The module was installed in the ISP panel, the only question is that the domain itself will still have a binding to a paid certificate?

Answer 1

Of course it is possible. What was the problem?

sudo ./certbot-auto certonly --agree-tos --rsa-key-size 4096 -m [email protected] -d subdomain.mydomain.com --renew-by-default

Answer 2

It is worth saying that there is a limitation from Let's Encrypt - no more than 39 certificates per domain. You may encounter this problem if you need to create a large number of regional subdomains.