How to enable/disable SNI support on the Plesk server

Question

How to enable/disable SNI support on the Plesk server?

Answer

By default, on clean Plesk installations (Linux and Windows) the support for SNI is turned on.

In case of Plesk upgrade on Windows from version 11.0 or earlier, the support for SNI is switched off.
It can be turned on in Tools & Settings > Server Settings.

To enable SNI support on Plesk for Linux:

1. Connect to the server using SSH.

2. Change SNI_SUPPORT value to true:

   # vi /etc/psa/psa.conf
   SNI_SUPPORT true

   Note: to disable change value to false.

3. Restart psa service:

   # service psa restart

The SSL support with SNI is possible only if the following requirements are met:

1. The operating system of Plesk server supports SNI.
   • Linux systems.
   • Windows Server 2012 and above.
2. Users’ browsers support SNI.

Note: most modern web browsers, starting from IE 7, Firefox 2.0, Opera 8.0, and Chrome 1.0, support SNI, unless they are run on Windows XP. To learn more about SNI and the client software that supports it, refer to http://en.wikipedia.org/wiki/Server_Name_Indication

If SNI is not supported and Plesk administrator assigned an SSL certificate to a website hosted on a shared IP address, Plesk will associate that certificate with all other websites hosted on this IP address. In the same case, hosting customers with shared IP addresses will not be able to assign SSL certificates to their sites: the Websites & Domains > example.com > Secure Your Sites button will be hidden in their Control Panel.

For instructions on assigning SSL certificates to websites, refer to Plesk Administrator’s Guide.