解决iredmail下postfix发送邮件时报错[need fully-qualified hostname]

iredmail配置好后，尝试从一客户端的OE中发送邮件，结果报错，在mail主机中查看tail /var/log/maillog，发现如下错误信息：

Oct  :: mail2 postfix/smtpd[]: connect from unknown[192.168.5.240]
Oct  :: mail2 postfix/smtpd[]: NOQUEUE: reject: RCPT from unknown[192.168.5.240]:  5.5. <dzDevelop>: Helo command rejected: need fully-qualified hostname; from=<lon@mail2.yinghuan.com> to=<lon@mail2.yinghuan.com> proto=ESMTP helo=<dzDevelop>
Oct  :: mail2 postfix/smtpd[]: NOQUEUE: reject: RCPT from unknown[192.168.5.240]:  5.5. <dzDevelop>: Helo command rejected: need fully-qualified hostname; from=<lon@mail2.yinghuan.com> to=<gng@yinghun.com> proto=ESMTP helo=<dzDevelop>
Oct  :: mail2 postfix/smtpd[]: disconnect from unknown[192.168.5.240]
Oct  :: mail2 postfix/smtpd[]: connect from unknown[192.168.5.240]
Oct  :: mail2 postfix/smtpd[]: NOQUEUE: reject: RCPT from unknown[192.168.5.240]:  5.5. <dzDevelop>: Helo command rejected: need fully-qualified hostname; from=<lon@mail2.yinghuan.com> to=<lon@mail2.yinghuan.com> proto=ESMTP helo=<dzDevelop>
Oct  :: mail2 postfix/smtpd[]: NOQUEUE: reject: RCPT from unknown[192.168.5.240]:  5.5. <dzDevelop>: Helo command rejected: need fully-qualified hostname; from=<lon@mail2.yinghuan.com> to=<gng@yinghun.com> proto=ESMTP helo=<dzDevelop>

经过努力探索，发现只需要修改postfix的配置文件即可，我的版本postfix配置文件位于/etc/postfix/main.cf

用编辑器打开vim /etc/postfix/main.cf，找到smtpd_helo_restrictions这一行，按照下面修改后保存。

smtp_data_xfer_timeout = 600s
smtpd_helo_required = yes
#smtpd_helo_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_helo_hostname, reject_invalid_helo_hostname, check_helo_access pcre:/etc/postfix/helo_access.pcre
#上面一行修改下面的内容，去掉reject_non_fqdn_helo_hostname
smtpd_helo_restrictions = permit_mynetworks, permit_sasl_authenticated,  reject_invalid_helo_hostname, check_helo_access pcre:/etc/postfix/helo_access.pcre

重新启动postfix

service postfix restart

再次发送，ok了