[Mail] 请SENDMAIL高手会诊！

[weixin_38058939]

我的OS是Red Hat Linux release 7.3，邮件系统是用的SENDMAIL。 客户端用的FOXMAIL 4.2
以前邮件都是正常的，可最近给外面邮箱发邮件，外面邮箱经常收不到，我们发的信。
我们内部收发是正常的，也能收到外面的邮箱的信。
如果我给外面邮箱发信时候，使用“特快专递”功能，外面的邮箱也能收到信。

我测试了 一些结果如下：

[root@www root]# nslookup 163.com
Note:  nslookup is deprecated and may be removed from future releases.
Consider using the `dig' or `host' programs instead.  Run nslookup with
the `-sil[ent]' option to prevent this message from appearing.
Server:         61.155.111.66
Address:        61.155.111.66#53

Non-authoritative answer:
Name:   163.com
Address: 202.106.185.77

[root@www root]# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost (127.0.0.1).
Escape character is '^]'.
220 www.chiefpower.com ESMTP Sendmail 8.11.6/8.11.6; Mon, 17 Feb 2003 12:18:04 +
0800
500 5.5.1 Command unrecognized: "hello"
ehlo hello
250-www.chiefpower.com Hello localhost [127.0.0.1], pleased to meet you
250-ENHANCEDSTATUSCODES
250-8BITMIME
250-SIZE
250-DSN
250-ONEX
250-ETRN
250-XUSR
250-AUTH GSSAPI LOGIN PLAIN
250 HELP

[root@www root]# telnet localhost 110
Trying 127.0.0.1...
Connected to localhost (127.0.0.1).
Escape character is '^]'.
+OK POP3 localhost v2001.78rh server ready