About Server Name Indication (SNI) : - this extension to the TLS protocol must be enabled to load some https URLs (for websites deployed with different certificats and host names on the same shared IP address), otherwise loading fails with errors such as "Received fatal alert: handshake_failure". - But it can be necessary to disable it in order to load some https URLs served by old and misconfigured web servers, otherwise loading fails with the exception javax.net.ssl.SSLProtocolException: "handshake alert: unrecognized_name". - Controlling SNI extension activation can also be done with the JVM option jsse.enableSNIExtension, but in that case a server restart is required when you want to modify the setting and it is not customizable per http client (general or for remote Solr). + this extension to the TLS protocol must be enabled to load some https URLs (for websites deployed with different certificats and host names on the same shared IP address), otherwise loading fails with errors such as Received fatal alert: handshake_failure. + But it can be necessary to disable it in order to load some https URLs served by old and misconfigured web servers, otherwise loading fails with the exception javax.net.ssl.SSLProtocolException: "handshake alert: unrecognized_name". + Controlling SNI extension activation can also be done with the JVM option jsse.enableSNIExtension, but in that case a server restart is required when you want to modify the setting and it is not customizable per http client (general or for remote Solr).