Some of you that use SEMrush might have noticed this;
“3 subdomains don’t support HSTS”
So HTTP Strict Transport Security (HSTS as we call it), this is a quick and easy fix and will help remove those notifications.
Firstly, you must have a SSL certificate enabled, without one (and enabling HSTS) will break your site.
What is HSTS
HTTP Strict Transport Security (HSTS) instructs web browsers to only use secure connections for all future requests when communicating with a web site. Doing so helps prevent SSL protocol attacks, SSL stripping, cookie hijacking, and other attempts to circumvent SSL protection.
How do I enable HSTS
When HSTS is enabled for a site, web browsers automatically change any insecure requests (http://) to secure requests (https://). All you need to do to enable HSTS is add a header to your site’s .htaccess file. Web browsers read the .htaccess file and recognize this header, then it’ll take care of the rest without any further intervention on your part.
To enable HSTS for your site, follow these steps:
- Using SSH or the File Manager, navigate to the ~/httpdocs directory.
- Open the text editor to open the .htaccess file.
If the .htaccess file does not already exist, create it.
- Copy the following line, and then paste it into the .htaccess file:
Header set Strict-Transport-Security "max-age=31536000" env=HTTPS
- Save your changes to the .htaccess file. HSTS is now enabled for your site.
When the web server sends this header, any browser that accesses the site over HTTPS will be unable to access the unsecured HTTP site for the specified length of time (in this case, 31,536,000 seconds, or one year). Therefore, as soon as you enable HSTS, you should not stop using SSL on your site. If you do, returning visitors will be unable to access your site.
One more SEO problem fixed!