ClickHouse/tests/integration/test_postgresql_protocol/configs/ssl_conf.xml

<?xml version="1.0"?>
 <yandex>
     <!-- Used with https_port and tcp_port_secure. Full ssl options list: https://github.com/ClickHouse-Extras/poco/blob/master/NetSSL_OpenSSL/include/Poco/Net/SSLManager.h#L71 -->
     <openSSL>
         <server> <!-- Used for https server AND secure tcp port -->
             <!-- openssl req -subj "/CN=localhost" -new -newkey rsa:2048 -days 365 -nodes -x509 -keyout /etc/clickhouse-server/server.key -out /etc/clickhouse-server/server.crt -->
             <certificateFile>/etc/clickhouse-server/config.d/server.crt</certificateFile>
             <privateKeyFile>/etc/clickhouse-server/config.d/server.key</privateKeyFile>
             <!-- openssl dhparam -out /etc/clickhouse-server/dhparam.pem 4096 -->
             <dhParamsFile>/etc/clickhouse-server/config.d/dhparam.pem</dhParamsFile>
             <verificationMode>none</verificationMode>
             <loadDefaultCAFile>true</loadDefaultCAFile>
             <cacheSessions>true</cacheSessions>
             <disableProtocols>sslv2,sslv3</disableProtocols>
             <preferServerCiphers>true</preferServerCiphers>
         </server>
     </openSSL>
 </yandex>