If you’re using a web application that serves multiple domains, then it’s easy to install and configure SSL certificates for all the domains.

First, you need to install and configure your web application such, as WordPress multisite, on your server. You can follow the steps in this article for multisite reference: How to Setup WordPress Multisite Network. Make sure you choose the subdomain option for your multisite network, and enable wildcard subdomains on your DNS provider.

After you have set up your application, you can add SSL certificates for your main domain and subdomains using Let’s Encrypt, Custom SSL, or simply use RunCloud’s self signed certificates.

To do this, go to SSL/TLS under your web application and make sure your domain and subdomains are accessible in your browser.

Then select your desired SSL provider for your SSL certificate. In the following example we are using the RunCloud’s self signed certificate for demonstration purposes.

After you have configured the settings, click on “Deploy SSL” to save the changes.

Wait for a few minutes until the SSL certificate is applied to your web application. You can check the status of your SSL certificate under SSL/TLS. Once it’s done, all the sub-domains on your website will be secure and displayed over HTTPS.