Just for simplicity sake, I always use the command above on fresh machines, but if you already have a certificate, it doesn’t hurt anything to revoke the old then request a wildcard cert. It will cover example.com, www.example.com and anyothersubdomain.example.com. Also means you shouldn’t have to update any web config files and the cert will auto renew without any problems.
This approach could be a problem if the old certificate is still referenced by a web server configuration file, because the web server may be unable to start after the old certificate file has been deleted.
I don’t think it would. The file paths would be the same because it wouldn’t append that “-0001”
When you restart the web server it should still be able to find the cert files, because they’ll be in the same place.
Sure, but if you use --nginx or --apache (or -a nginx or -a apache), Certbot needs to restart the web server before the new certificate has been issued (as part of the process of requesting it).