Learning how to check an intermediate certificate is important especially after installing a new SSL cert. If your full certificate chain is not installed correctly on the server this can cause a number of client-side issues. These issues can range from un-trusted connection messages, certificate errors, and more.
Verify the Certificate Chain is Installed Correctly
The easiest way to verify that your complete certificate chain is installed correctly is to use an online tool. Below are a number of great tools that you can use to verify that your SSL certificate and chain are set up correctly.
This is a comprehensive test and definitely one of the most thorough online tests available. It will check both IPv4 and IPv6 (if applicable) of your server and provide you with detailed analysis and a letter grade based upon the effectiveness of your SSL installation and configuration.
The SSL Checker by SSL Shopper is a basic tool that will query your site and provide quick analysis on your SSL certificate. It will check the complete chain and also verify if it is installed correctly.
The SSL Installation Diagnostics tool is a good tool as it will check that you SSL certificate chain is installed correctly and it will also check your server for known vulnerabilities (such as Heartbleed). This tool will also provide you with a list of protocols that you server is configured for as well as a list of supported cyphers.
Fixing Discovered Issues
If any of the above tools report an issue with your certificate whether it be an incorrectly installed certificate chain, vulnerability, etc. you need to fix the issue right away to avoid any visitor interruption on your website. This will ensure a smooth and pleasant experience for your website users.