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安装snap

sudo apt update

sudo apt install snapd

sudo snap install core

 sudo snap refresh core
 
 

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sudo snap install --classic certbot

sudo ln -s /snap/bin/certbot /usr/bin/certbot

为Nginx部署

sudo certbot --nginx

安装后的提示信息

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/iseenu.icu/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/iseenu.icu/privkey.pem
   Your certificate will expire on 2021-08-20. To obtain a new or
   tweaked version of this certificate in the future, simply run
   certbot again with the "certonly" option. To non-interactively
   renew *all* of your certificates, run "certbot renew"
 - If you like Certbot, please consider supporting our work by:

   Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
   Donating to EFF:                    https://eff.org/donate-le

sudo certbot certonly --nginx

sudo certbot renew --dry-run

Q.E.D.