Hi Dave, Thanks for your comments. I am not really familiar with OpenSSL, so some parts of my descriptions may not be not very clear. Right, I am talking about s_server subcommand. You mentioned that there is no change in this area. However I can easily show something is change using s_server subcommand. I am using original OpenSSL code to build my 'openssl', to this change is not from me. 1) 1.0.1l ./apps/openssl s_server -ssl3 -cert certdb/ssl_server.pem -WWW -CAfile certdb/cafile.pem Using default temp DH parameters Using default temp ECDH parameters ACCEPT 2) 1.0.2 ./apps/openssl s_server -ssl3 -cert certdb/ssl_server.pem -WWW -CAfile certdb/cafile.pem Using default temp DH parameters ACCEPT Note that, in 1.0.2, openssl doesn't print out 'Using default temp ECDH parameters'. I checked related code in s_server.c and ssl_conf.c, There are some updates. Some related code is moved from s_server.c to ssl_conf.c. However I haven't found the root cause of this change. I encountered a similar issue when upgrading from OpenSSL 1.0.1l to 1.0.1m. I paste my analysis and fix below. After I applied my fix, the issue disappeared. 1) Analysis File s_server.c was updated in OpenSSL 1.0.1m. Variable 'no_ecdhe' was uninitialized after the update. This causes the condition of the if statement (if (!no_ecdheon) {...}) on line 1682 not to be true. Then ECDHE-RSA-AES256-SHA is not the default temp ECDH parameters of 'openssl s_server' any more. 2) Fix 273 diff -wruN openssl-1.0.1m.original/apps/s_server.c openssl-1.0.1m.working/apps/s_server.c 274 --- openssl-1.0.1m.original/apps/s_server.c 2015-03-19 06:37:10.000000000 -0700 275 +++ openssl-1.0.1m.working/apps/s_server.c 2015-05-25 01:46:35.000000000 -0700 276 @@ -998,7 +998,7 @@ 277 int off = 0; 278 int no_tmp_rsa = 0, no_dhe = 0, nocert = 0; 279 #ifndef OPENSSL_NO_ECDH 280 - int no_ecdhe; 281 + int no_ecdhe = 0; 282 #endif 283 int state = 0; 284 const SSL_METHOD *meth = NULL; I noticed that the issue in 1.0.2 is not the same as the issue in 1.0.1m. The issue started to appear in 1.0.2 rather than 1.0.2a. Thanks, Aaron -- View this message in context: http://openssl.6102.n7.nabble.com/The-behavior-change-of-command-line-utility-openssl-tp58557p58631.html Sent from the OpenSSL - User mailing list archive at Nabble.com.