Testing TLS Protocol Versions with cURL

Anthony Nocentino has a tip for us:

Ever need to set your web server a specific protocol version of TLS for web servers and need a quick way to test that out to confirm? Let’s check out how to use curl to go just that.

This code here uses curl with the parameters --tlsv1.1 --tls-max 1.1, which will force the max TLS protocol version to 1.1. Using the --verbose parameter gives you the ability to see the TLS handshake and get the output sent to standard out.

Also, check the comments for a very helpful addendum.

I should note that cURL is built into Windows 10 as of v1803, and it’s been a part of MacOS and Linux for a long, long time.