On Sat, Mar 16, 2019 at 09:06:06AM +0900, Atsuhito Kohda wrote: > Hi Sebastian, > > On Fri, 15 Mar 2019 22:08:13 +0100, Sebastian Andrzej Siewior wrote: > > > Do you have somewhere more information what failed on the fetchmail > > side? > > Yes, I have error messages of fetchmail but they contains > some Japanese characters. (I added simple translations of > them but not precise translations.) > > fetchmail: System error during SSL_connect(): 接続が相手からリセットされました > fetchmail: SSL による接続に失敗しました。 > fetchmail: socketエラーが **server name** よりメールを受信している最中に発生しました。 > fetchmail: Query status=2 (SOCKET) > > line #1:connection is reset by server > line #2:connection by SSL is failed > line #3:during receiving mail from **server name**, a socket error occured > > > Is the server using by any chance a small DH key? > > Not sure but on the server dovecot (of Debian package) is running.
So from what I understand, the problem is really on the dovecot side. What does dovecot's log show? Dovecot can configure DH, which seems to default to: ssl_dh = </usr/share/dovecot/dh.pem That file should be fine, it's 4096 bit. Kurt