能否给个排查思路?我目前观察163的邮箱很多会这样

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- iRedMail 版本号:0.94
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张工您好:
我自建的iredmail邮箱,在mailq中总是有大量邮件,有发出去的,也有收进来的,百思不得其解。
日志如下,请帮忙解惑,谢谢

mailq
45F88A0536  3764952 Wed May 18 16:15:09  shixy@xxx.cn
(host 163mx01.mxmail.netease.com[220.181.14.135] said: 421 Read data from client error (in reply to end of DATA command))
                                         pdh1000@163.com
11EA1A05A9  3764916 Wed May 18 16:16:08  shixy@xxx.cn
(host 163mx01.mxmail.netease.com[220.181.14.140] said: 421 Read data from client error (in reply to end of DATA command))
                                         pdh1000@163.com
38DF5A0567   457824 Wed May 18 16:16:03  SOMYTEC@slx.cn
(host 192.168.0.146[192.168.0.146] said: 451 4.3.5 Server configuration error (in reply to RCPT TO command))
                                         hr@xxx.cn
B2F86A0597     6870 Wed May 18 16:14:42  MAILER-DAEMON
(host 163mx02.mxmail.netease.com[220.181.14.145] said: 421 Read data from client error (in reply to end of DATA command))
                                         13910460377@163.com

cat /var/log/maillog |grep 45F88A0536
May 18 19:54:12 mailgw postfix/qmgr[11215]: 45F88A0536: from=<shixy@xxx.cn>, size=3764952, nrcpt=1 (queue active)
May 18 19:54:15 mailgw postfix/smtp[1976]: 45F88A0536: host 163mx03.mxmail.netease.com[220.181.14.164] said: 421 Read data from client error (in reply to end of DATA comman
d)May 18 19:54:19 mailgw postfix/smtp[1976]: 45F88A0536: to=<pdh1000@163.com>, relay=163mx01.mxmail.netease.com[220.181.14.135]:25, delay=13150, delays=13143/2.9/0.82/3.2, ds
n=4.0.0, status=deferred (host 163mx01.mxmail.netease.com[220.181.14.135] said: 421 Read data from client error (in reply to end of DATA command))