Recommended Steps for Subdomain

[yalfy]

My domain is www.careshare360.com. I’m running on an EC2 instance and have a second instance for a subdomain (app.careshare360.com).

Both are running nginx and both are currently separately encrypted.

I am wondering if there is a better/recommended procedure for securing both. More importantly, should I have some kind of link between the two, or can I keep the configuration as-is: each instance controlling its own certificate?

I was attempting to add the subdomain to my main server by running:
sudo certbot certonly --nginx -d www.careshare360.com,careshare360.com,app.careshare360.com --dry-run

I then received an invalid response from the .well-known/acme-challenge.

I’m not entirely sure I need to add the subdomain to the main domain, but others attempting to access the site had some suspicious warnings on both domains post-separate issuance.

[_az]

@yalfy

I’m not entirely sure I need to add the subdomain to the main domain

You don't - use only names that the server is actually going to be serving traffic for.

@yalfy

others attempting to access the site had some suspicious warnings on both domains post-separate issuance

Do you have a screenshot of the warnings?

[yalfy]

@_az

Do you have a screenshot of the warnings?

[_az]

That’s the error when you tried to create a certificate containing the app subdomain on your www server, right? That’s normal and expected.

Sorry, I was trying to ask about a screenshot of the “suspicious warnings” that the visitors to your site were encountering, when you had used separate certificates.

[yalfy]

@_az

That's the error when you tried to create a certificate containing the app subdomain on your www server, right? That's normal and expected.

Correct, and figured as much!

Thanks for the response.

As far as the other screenshots - looks like it cannot be reproduced. I did not experience the issues myself.