Thank you, I very much appreciate your reply. It certainly wasn’t the date of the computer. I went into the server, stopped Nginx, and ran this command;
sudo -H ./letsencrypt-auto certonly --standalone -d yourdomain.com -d www.yourdomain.com
It tolled me the certificate didn’t need renewing, so I left it, then when I restarted Nginx everything was fine and the warning in the browser went away.
It was scary because I didn’t know what to do, at first I tried to redirect the https to http, to give me some breathing room but even that wouldn’t work - It just makes me feel like I shouldn’t be doing this for clients, but I like saving them money if I can, but at what cost… that’s why I’m now taking an Ubuntu crash course. (I copy and pasted code from a tutorial to get SSL to work, and it had been working fine up until today.)
So, if I hadn’t have restarted the server would this have just resolved it’s self eventually? How can I prevent this from happing again?
I have this script set up to auto renew;
/opt/letsencrypt/letsencrypt-auto renew --agree-tos --email email@example.com