On Wed, 2017-03-29 at 16:52 +0800, Siyuan Ren wrote: > The server shows a useless log message > > > disconnect user '166F57A07AAF' (909) from > > 2402:f000:5:7a01:510c:779b:671a:a363 with IP 10.44.3.212 (reason: > > unspecified error, time:?????1s) > > Any recommendation on what tools I could use to debug the connection? One is use wireshark and check the TLS session from the "outside", and another is increase verbosity on both the server and the client. On the server you can do that with '-d', and go gradually from 4 to 9 until something interesting pops up. regards, Nikos