Telnet测试pop3

Question

我在使用POP3接收来自VPS的电子邮件方面有问题.在邮件应用程序中，我得到消息，连接失败，我应该检查登录和电子邮件无论如何，它是好的。我试着通过bash检查一下：

telnet mail.inovestudio.com 110
Trying 5.135.147.5... Connected to mail.inovestudio.com. Escape character is '^]'.
+OK Dovecot ready.

USER hello@inovestudio.com
+OK

PASS here_i_put_some_pass** 
Connection closed by foreign host.

你知不知道，它为什么会这样，我怎么能修好它？谢谢。

解决方法: in /etc/dovecot/con.d/10-auth.conf，我使用以下方法：

disable_plaintext_auth = yes

mail.log

Nov 10 05:41:33 vps22346 dovecot: auth: Error: BUG: Authentication client sent unknown handshake command: REQUEST?3110993921?677?1?0b0656b72c084511c2988b99b346c1a5
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Authentication server didn't send valid SPID as expected: MECH   PLAIN   plaintext
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Disconnected from auth server, aborting (client-pid=677 client-id=1)
    Nov 10 05:41:33 vps22346 dovecot: pop3-login: Internal login failure (pid=677 id=1) (internal failure, 1 succesful auths): user=<hello@inovestudio.com>, method=LOGIN, rip=188.175.31.165, lip=5.135.147.5, mpid=680, TLS, session=<+fv6UigkNAC8rx+l>
    Nov 10 05:41:33 vps22346 dovecot: auth: Warning: auth client 677 disconnected with 1 pending requests: EOF
    Nov 10 05:41:33 vps22346 dovecot: auth: Error: BUG: Authentication client sent unknown handshake command: REQUEST?602800129?676?1?25bf41ba73464024b67fff41742cba4f
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Authentication server didn't send valid SPID as expected: MECH   PLAIN   plaintext
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Disconnected from auth server, aborting (client-pid=676 client-id=1)
    Nov 10 05:41:33 vps22346 dovecot: pop3-login: Internal login failure (pid=676 id=1) (internal failure, 1 succesful auths): user=<kozusnik@inovestudio.com>, method=LOGIN, rip=188.175.31.165, lip=5.135.147.5, mpid=681, TLS, session=<LPr6UigkMwC8rx+l>
    Nov 10 05:41:33 vps22346 dovecot: auth: Warning: auth client 676 disconnected with 1 pending requests: EOF
    Nov 10 05:41:33 vps22346 dovecot: auth: Error: BUG: Authentication client sent unknown handshake command: REQUEST?1481113601?679?1?6be03e001c9de41da5fc46999f937597
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Authentication server didn't send valid SPID as expected: MECH   PLAIN   plaintext
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Disconnected from auth server, aborting (client-pid=679 client-id=1)
    Nov 10 05:41:33 vps22346 dovecot: pop3-login: Internal login failure (pid=679 id=1) (internal failure, 1 succesful auths): user=<info@inovestudio.com>, method=PLAIN, rip=188.175.31.165, lip=5.135.147.5, mpid=682, TLS, session=<G9D7UigkNQC8rx+l>
    Nov 10 05:41:33 vps22346 dovecot: auth: Warning: auth client 679 disconnected with 1 pending requests: EOF
    Nov 10 05:41:33 vps22346 dovecot: auth: Error: BUG: Authentication client sent unknown handshake command: REQUEST?2768109569?683?1?bd65b7382983d84dbf6d3c710d7bf9d3
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Authentication server didn't send valid SPID as expected: MECH   PLAIN   plaintext
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Disconnected from auth server, aborting (client-pid=683 client-id=1)
    Nov 10 05:41:33 vps22346 dovecot: pop3-login: Internal login failure (pid=683 id=1) (internal failure, 1 succesful auths): user=<hello@inovestudio.com>, method=PLAIN, rip=188.175.31.165, lip=5.135.147.5, mpid=685, TLS, session=</r0AUygkNgC8rx+l>
    Nov 10 05:41:33 vps22346 dovecot: auth: Warning: auth client 683 disconnected with 1 pending requests: EOF
    Nov 10 05:41:33 vps22346 dovecot: auth: Error: BUG: Authentication client sent unknown handshake command: REQUEST?1966735361?684?1?81003e4dfc94424d81de1215228fe809
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Authentication server didn't send valid SPID as expected: MECH   PLAIN   plaintext
    Nov 10 05:41:33 vps22346 dovecot: pop3: Error: Disconnected from auth server, aborting (client-pid=684 client-id=1)
    Nov 10 05:41:33 vps22346 dovecot: pop3-login: Internal login failure (pid=684 id=1) (internal failure, 1 succesful auths): user=<kozusnik@inovestudio.com>, method=PLAIN, rip=188.175.31.165, lip=5.135.147.5, mpid=686, TLS, session=</70AUygkNwC8rx+l>
    Nov 10 05:41:33 vps22346 dovecot: auth: Warning: auth client 684 disconnected with 1 pending requests: EOF
    Nov 10 05:42:26 vps22346 postfix/anvil[509]: statistics: max connection rate 1/60s for (smtps:188.175.31.165) at Nov 10 05:39:06
    Nov 10 05:42:26 vps22346 postfix/anvil[509]: statistics: max connection count 1 for (smtps:188.175.31.165) at Nov 10 05:39:06
    Nov 10 05:42:26 vps22346 postfix/anvil[509]: statistics: max cache size 1 at Nov 10 05:39:06

当我尝试执行这个：service postfix restart时，它返回：

[ ok ] Stopping Postfix Mail Transport Agent: postfix. 
[ ok ] Starting Postfix Mail Transport Agent: postfix. 
root@vps22346:/# 2015 Nov 17 09:47:16 vps22346 lda: Fatal: Internal error occurred. Refer to server log for more information.

Answer 1

似乎dovecot被配置为拒绝非安全身份验证，这很好。要测试，请使用

openssl s_client -connect mail.inovestudio.com:995

你应该看到很多信息，但应该以

+OK Dovecot ready.

在这里你可以试试

USER hello@inovestudio.com
PASS yourcleartextpassword