Thanks Andy. Indeed a setting of the form security.server.disabled.protocols=SSL|SSLv2|SSLv3|TLSv1|TLSv1.1 disables all the unwanted protocols. But this cuts all the communication with the nodes, since for some reason TLSv1.2 isn't active by default and there's no option to enable protocols. So I ended up creating my own Ambari fork, where I explicitly enable TLSv1.2 in the source code. Then, disabling the SSL family and the old TLS protocols leaves only TLSv1.2 as intended. Problem solved. ... View more

@Andy LoPresto: It's not that I'm trying to open multiple HTTPS connections. Ports 8440 and 8441 are used by the Ambari server for secure (HTTPS) communication with the agents in the cluster, see here. My question is how to enable TLSv1.2 transport for these two secure connections. ... View more