Is it possible to auto renew the certificate for every three months whenever the certificate is going to expire?
Yes, though autorenew typically happens every 60 days just to be safe. You need an installed ACME Let’s Encrypt client (like certbot) that can automatically create the challenge files for you that are needed to prove control of the domain.
If you’re renewing wildcard (*.) certificates, this can be more challenging to autorenew because they require DNS TXT records to be created rather than simply challenge files.
It all depends on your situation. Most of all, do you have root access to your server? Or are you on shared hosting without root access and are you at the peril of your hosting provider?
If any of these are a problem, I’ve probably still got a solution for you, but @Osiris probably won’t like it.
My alternative solution isn’t automated and therefore would not help under the conditions @Osiris has outlined. Then again, there really isn’t much of a solution under all of those conditions.
Depends on what you’re going to say, specifically as @RAYA asks for automated renewal.
If you have a solution for automated renewal on shared hosting without root access and some kind of custom build control panel without any TLS option what so ever: I’m all ears!
True that. The golden goose I have not.
When you said “shared hosting”, do you mean to deploy same wildcard certificate on different hosted machines?
No, with shared hosting I mean a webserver operates by a hosting company which enables multiple users to have their website hosted on that server. Those users normally won’t have root access to that server for obvious reasons. Most of the time they’ll have some kind of configuration panel like cPanel or the likes.
Do we have any documentation or steps to configure ACME Let’s Encrypt client (like certbot)?
That’s a very, very broad question without a direct answer to it.