今天使用了几种不同的“DNS 健康测试”,我收到两份报告称 SMTPD 问候语是错误的/配置错误的。
例如,测试http://www.dnsqueries.com说我没有通过这项特定测试,然后接着说:
垃圾邮件识别软件和 RFC821 4.3(还有 RFC2821 4.3.1)规定,SMTP 问候语中给出的主机名必须具有指向同一服务器的 A 记录。
我正在运行 Bind 作为 ns1.smoothstoneservices.com 和 ns2.smoothstoneservices.com 的名称服务器,并且邮件服务器正在运行 Postfix。
操作系统是CentOS。
查看 /etc/postfix/main.cf 中的 smtpd_banner 指令,它设置为:mail.smoothstoneservices.com
DNS 包括“mail.smoothstoneservices.com”(smtpd 问候语)以及 myers.smoothstoneservices.com(主机名)的 A 记录。
这是我的区域文件的内容:
$TTL 1H
@ IN SOA ns1.smoothstoneservices.com. admin.smoothstoneservices.com. (
2012021115; serial
1800 ; refresh
400 ; retry
1209600; expire
3600 ; Minimum
)
IN NS ns1.smoothstoneservices.com.
IN NS ns2.smoothstoneservices.com.
@ IN MX 0 mail.smoothstoneservices.com.
@ IN A 69.164.221.183
@ IN TXT "v=spf1 a mx ip4:69.164.221.183 -all"
localhost IN A 127.0.0.1
myers IN A 69.164.221.183
ns1 IN A 69.164.221.183
ns2 IN A 66.228.59.103
mail IN A 69.164.221.183
{Some info snipped that you don't need to know}
测试http://mxtoolbox.comMX 和邮件服务器健康状况表明一切正常。
但由于我在两个独立的“DNS健康”测试/网站上看到了类似的“错误”,所以我怀疑我可能遗漏了一些东西。
我很困惑。你觉得有什么问题吗?你的看法是什么?
答案1
好的,现在谈谈你的 SMTP 问候语的问题
- 如果您从 69.164.221.183 发送外发邮件
- 如果您 EHLO 为 mail.smoothstoneservices.com
你可能会遇到一些麻烦一丝不苟的完美主义者因为,正式来说,对于 69.164.221.183,在 EHLO 中命名为 mail.smoothstoneservices.com,我们会看到
Quering 8.8.4.4 for {183.221.164.69.in-addr.arpa.,PTR}
...
Answers for 183.221.164.69.in-addr.arpa.:
-> [PTR] myers.smoothstoneservices.com.
并且 mail.smoothstoneservices.com!=myers.smoothstoneservices.com 并且您无法在域区域中进行更改,它必须由 221.164.69.in-addr.arpa 区域的维护者进行更改
答案2
奇怪 - 我刚刚尝试了 smtp 测试http://www.dnsqueries.com/为了你和我,一切都已清楚。
Connection Test I was able to connect on port 25 to mail.smoothstoneservices.com
HostName in Greeting The hostname in the greeting message is
mail.smoothstoneservices.com
Accepts Null <> Sender The SMTP server is accepting NULL <> Sender
Accepts Mail to Postmaster The SMTP server is accepting mails to [email protected]. This is a good thing, as this addres is used to send out system communications
Accepts Mail to Abuse The SMTP server is accepting mails to [email protected]. This is a good thing, as this address is used to send out abuse communications
Accepts Mail to domain literals The SMTP server is accepting mails to postmaster@[IP_ADDRESS]. This is a good thing, as this address is used by people that don't know your domain name!
Is Open Relay I have tried to send out email through the SMTP server and i wasn't able. This is a good thing, as it seems that your server isn't an open relay.
另外,我刚刚通过 telnet 连接到 69.164.221.183 的 25 端口,并获得了 220 mail.smoothstoneservices.com
我想知道之前是否出了问题,而您现在检查时得到的是缓存结果。
编辑:更奇怪 - 我刚刚用测试设置检查了 www.dnsqueries.com,其中 A 记录与 SMTP 问候语中指定的主机名不匹配,并且对此感到满意。