CentOS下通過postfix使用自己的gmail郵箱發送郵件

起因：

[root@backup ~]# echo 123|mail -s "123" [email protected]

[root@backup ~]# smtp-server: 530 5.7.0 Must issue a STARTTLS command first. 71sm664699pfs.63 - gsmtp

"/root/dead.letter" 11/317

. . . message not sent.

    之前一直使用的qq郵箱給自己發送郵件，做資料備份用，今天想把qq郵箱換成gmail郵箱，結果出現了上面的錯誤，網上查找了下資料終于得以解決，但中途坑比較多，總結一下友善日後遇坑。

    為友善檢視，用紅色表示輸入的指令，藍色表示輸入的内容

1、在/etc/postfix/main.cf檔案末尾添加如下字段。

vi /etc/postfix/main.cf

smtp_sasl_security_options = noanonymous

relayhost = [smtp.gmail.com]:587

smtp_use_tls = yes

smtp_tls_CAfile = /etc/postfix/cacert.pem

smtp_sasl_auth_enable = yes

smtp_sasl_password_maps = hash:/etc/postfix/sasl/passwd

2、配置SASL認證

建立passwd檔案并添加賬号密碼資訊

mkdir -p /etc/postfix/sasl

vi /etc/postfix/sasl/passwd

[smtp.gmail.com]:587 你的郵箱:應用專用密碼

注意郵箱賬号和密碼之間的“:"，不要漏掉。例如：我公司購買的google郵箱服務，我生成的密碼是123qwe則配置[smtp.gmail.com]:587 [email protected]:123qwe

由于google的安全限制，使用非web方式使用需要設定【應用專用密碼】

應用專用密碼生成網站：https://security.google.com/settings/security/apppasswords

3、更改檔案權限

chmod 600 /etc/postfix/sasl/passwd

4、建立查找表

postmap /etc/postfix/sasl/passwd

5、生成CA憑證

cd /etc/pki/tls/certs

make 你的名字.pem               #例如：我叫小明，則 make xiaoming.pem

umask 77 ; \

    PEM1=`/bin/mktemp /tmp/openssl.XXXXXX` ; \

    PEM2=`/bin/mktemp /tmp/openssl.XXXXXX` ; \

    /usr/bin/openssl req -utf8 -newkey rsa:2048 -keyout $PEM1 -nodes -x509 -days 365 -out $PEM2 -set_serial 0 ; \

    cat $PEM1 >  xiaoming.pem ; \

    echo ""    >> xiaoming.pem ; \

    cat $PEM2 >> xiaoming.pem ; \

    rm -f $PEM1 $PEM2

Generating a 2048 bit RSA private key

....................................+++

....................................................................+++

writing new private key to '/tmp/openssl.gHSN9F'

-----

You are about to be asked to enter information that will be incorporated

into your certificate request.

What you are about to enter is what is called a Distinguished Name or a DN.

There are quite a few fields but you can leave some blank

For some fields there will be a default value,

If you enter '.', the field will be left blank.

Country Name (2 letter code) [XX]:cn

State or Province Name (full name) []:beijing

Locality Name (eg, city) [Default City]:beijing

Organization Name (eg, company) [Default Company Ltd]:gongsi

Organizational Unit Name (eg, section) []:it

Common Name (eg, your name or your server's hostname) []:xiaoming

Email Address []:[email protected]

cp /etc/pki/tls/certs/zhaoxinxing.pem /etc/postfix/cacert.pem

7、重新開機postfix服務

/etc/init.d/postfix restart

8、測試、完成