Connecting synology-ssh-server as root.
if you want to connect to synology ssh server, you mush login ssh-server as admin first.
and then, change as root. type this.
$ sudo -i
- root password is same with admin password.
you can sse that you did login as root. type following this.
$ /usr/syno/sbin/syno-letsencrypt renew-all -v
-v is debug mode. so you can see a log list what does it happen.
- you have to open 80 port to renew certification.
in my case, cert is not expired. so i will do next time. :) it's done. thank you.
// this let you know to renew certification automatically.
// you can check when it started, and when it expired.
echo | openssl s_client -connect