This article discusses Server Name Indication (SNI) support at A2 Hosting.
Server Name Indication (SNI) is an extension to the Transport Layer Security (TLS) protocol that enables servers to use multiple SSL certificates on one IP address. In practical terms, this means:
The answer to this question depends on two things: whether your A2 Hosting server supports SNI, and whether your site visitors use web browsers that support SNI.
The following A2 Hosting servers do not support SNI:
These servers run a version of OpenSSL that does not support SNI. Therefore, to install an SSL certificate on any of these servers, you must also purchase a dedicated IP address.
All other A2 Hosting servers support SNI, and do not require a dedicated IP address to install an SSL certificate.
In addition to server SNI support, users' web browsers must support SNI. Fortunately, almost all modern operating systems and web browsers support SNI. However, there are a few notable exceptions of browsers that do not support SNI:
If you have a significant number of visitors that use one or more of these browsers, SNI is probably not the best choice. You should purchase a dedicated IP address and use an SSL certificate without SNI instead.
For more information about SNI, please visit https://en.wikipedia.org/wiki/Server_Name_Indication.