Does it require internet connection to use it on local server?

[minamonfff]

let’s say i have set it up on a local server … will devices be able to access the https server without an internet connection?

[rg305]

You are being somewhat vague with your question.

1. your use of the term "it" leaves much to the imagination:
   "Does it require internet connection..."
   "let’s say I have set it up on a local server …"
2. you don't explain which client is intended to be used, nor which validation method, etc.

But to answer your question:

@minamonfff

will devices be able to access the https server without an internet connection?

That answer would be from basic routing 101 and DNS 101.
Given: LE certs are for DNS names [not IP addresses]

1. Can the devices resolve the DNS name to an IP?
2. Can the devices reach that IP?

If the answer to both is "yes", then yes; you can access the HTTPS server without an Internet connection.

So my first concern is in how would you get a valid cert from LE without an Internet connection...

[minamonfff]

@rg305

valid cert from LE without an Internet connection

i mean after setting it up and trying to visit the domain using any normal device win or whatever in a local network without internet connection .