我正在尝试在 debian squeeze 服务器上配置带有 SASL 身份验证的 postfix+dovecot。我可以从 roundcube 应用程序发送邮件，但根本无法接收邮件。
tail /var/log/mail.err 报告此情况：
dovecot：交付（[电子邮件保护]): userdb 查找：连接（/var/run/dovecot/auth-master）失败：没有此文件或目录
cat /mail.info | grep smtp
Jan 9 16:15:02 s1******** postfix/smtpd[11542]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:15:02 s1******** postfix/smtpd[11542]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:15:02 s1******** postfix/smtpd[11542]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:20:01 s1******** postfix/smtpd[12715]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:20:01 s1******** postfix/smtpd[12715]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:20:01 s1******** postfix/smtpd[12715]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:25:02 s1******** postfix/smtpd[13886]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:25:02 s1******** postfix/smtpd[13886]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:25:02 s1******** postfix/smtpd[13886]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:30:01 s1******** postfix/smtpd[15048]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:30:01 s1******** postfix/smtpd[15048]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:30:01 s1******** postfix/smtpd[15048]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:35:01 s1******** postfix/smtpd[16204]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:35:01 s1******** postfix/smtpd[16204]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:35:01 s1******** postfix/smtpd[16204]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: disconnect from localhost.localdomain[127.0.0.1]
cat /var/log/mail.err | grep smtp （请注意，自从我更改了一些配置文件并重新启动了 postfix 后，这种情况就没有发生）：
Jan 9 14:36:03 s1******** postfix/smtpd[18443]: fatal: no SASL authentication mechanisms
Jan 9 14:36:03 s1******** postfix/smtpd[18444]: fatal: no SASL authentication mechanisms
Jan 9 14:40:02 s1******** postfix/smtpd[19368]: fatal: no SASL authentication mechanisms
Jan 9 14:44:32 s1******** postfix/smtpd[20446]: fatal: no SASL authentication mechanisms
Jan 9 14:45:33 s1******** postfix/smtpd[20710]: fatal: no SASL authentication mechanisms
Jan 9 14:48:35 s1******** postfix/smtpd[23032]: fatal: no SASL authentication mechanisms
Jan 9 14:50:01 s1******** postfix/smtpd[23357]: fatal: no SASL authentication mechanisms
cat /var/log/mail.err | grep postfix
Jan 9 16:39:07 s1******** postfix/qmgr[30385]: 4F95F4865: from=<[email protected]>, size=6283, nrcpt=1 (queue active)
Jan 9 16:39:07 s1******** postfix/qmgr[30385]: D3EE14866: from=<[email protected]>, size=3030, nrcpt=1 (queue active)
Jan 9 16:39:07 s1******** postfix/qmgr[30385]: CA3F34861: from=<[email protected]>, size=6308, nrcpt=1 (queue active)
Jan 9 16:39:07 s1******** postfix/pipe[17148]: 4F95F4865: to=<[email protected]>, relay=dovecot, delay=4631, delays=4631/0.08/0/0.05, dsn=4.3.0, status=deferred (temporary failure)
Jan 9 16:39:07 s1******** postfix/pipe[17150]: D3EE14866: to=<[email protected]>, relay=dovecot, delay=4523, delays=4523/0.06/0/0.03, dsn=4.3.0, status=deferred (temporary failure)
Jan 9 16:39:07 s1******** postfix/pipe[17148]: CA3F34861: to=<[email protected]>, relay=dovecot, delay=4740, delays=4740/0.1/0/0.01, dsn=4.3.0, status=deferred (temporary failure)
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:40:02 s1******** postfix/smtpd[17370]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:44:07 s1******** postfix/qmgr[30385]: EA65C485F: from=<SRS0=7kfH=LC=gmail.com=user+gmcfv372c65e7b3345f7@srs.kundenserver.de>, size=3856, nrcpt=1 (queue active)
Jan 9 16:44:07 s1******** postfix/pipe[18291]: EA65C485F: to=<[email protected]>, relay=dovecot, delay=5805, delays=5805/0.06/0/0.02, dsn=4.3.0, status=deferred (temporary failure)
Jan 9 16:45:01 s1******** postfix/pickup[30384]: B8D7F4869: uid=0 from=<root>
Jan 9 16:45:01 s1******** postfix/cleanup[18526]: B8D7F4869: message-id=<20130109154501.B8D7F4869@s1********.onlinehome-server.info>
Jan 9 16:45:01 s1******** postfix/qmgr[30385]: B8D7F4869: from=<root@s1********.onlinehome-server.info>, size=687, nrcpt=1 (queue active)
Jan 9 16:45:01 s1******** postfix/smtpd[18531]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:45:01 s1******** postfix/smtpd[18531]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:45:01 s1******** postfix/smtpd[18531]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:45:01 s1******** postfix/cleanup[18526]: EB0254867: message-id=<20130109154501.B8D7F4869@s1********.onlinehome-server.info>
Jan 9 16:45:01 s1******** postfix/qmgr[30385]: EB0254867: from=<root@s1********.onlinehome-server.info>, size=851, nrcpt=1 (queue active)
Jan 9 16:45:01 s1******** postfix/local[18528]: B8D7F4869: to=<root@s1********.onlinehome-server.info>, orig_to=<root>, relay=local, delay=0.29, delays=0.12/0.1/0/0.07, dsn=2.0.0, status=sent (forwarded as EB0254867)
Jan 9 16:45:01 s1******** postfix/qmgr[30385]: B8D7F4869: removed
Jan 9 16:45:02 s1******** postfix/smtp[18537]: connect to aspmx.l.google.com[2a00:1450:400c:c03::1b]:25: Network is unreachable
Jan 9 16:45:02 s1******** postfix/smtp[18537]: EB0254867: to=<[email protected]>, orig_to=<root>, relay=aspmx.l.google.com[173.194.70.27]:25, delay=0.78, delays=0.01/0.06/0.27/0.44, dsn=2.0.0, status=sent (250 2.0.0 OK 1357746302 l1si174424993een.25)
Jan 9 16:45:02 s1******** postfix/qmgr[30385]: EB0254867: removed
Jan 9 16:50:02 s1******** postfix/smtpd[19667]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:50:02 s1******** postfix/smtpd[19667]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:50:02 s1******** postfix/smtpd[19667]: disconnect from localhost.localdomain[127.0.0.1]
Jan 9 16:55:01 s1******** postfix/smtpd[20814]: connect from localhost.localdomain[127.0.0.1]
Jan 9 16:55:01 s1******** postfix/smtpd[20814]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 9 16:55:01 s1******** postfix/smtpd[20814]: disconnect from localhost.localdomain[127.0.0.1]
谢谢