前言:
新上一臺阿里的云主機，提供web服務，各種環境搭建完成，能夠提供服務，沒想到在最后的監控環節遇到各種發郵件的坑，這里分享給大家，你是否也遇到這種坑？
網易163免費郵箱相關服務器信息：
一、安裝和配置:
1.1、安裝
[root@linux-node2 ~]# yum install mailx -y
Loaded plugins: fastestmirror, security
Setting up Install Process
Determining fastest mirrors
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
base | 3.7 kB 00:00
epel | 3.2 kB 00:00
epel/primary | 3.2 MB 00:00
epel 12521/12521
extras | 3.4 kB 00:00
icehouse | 2.9 kB 00:00
updates | 3.4 kB 00:00
updates/primary_ | 1.2 MB 00:00
Package mailx-12.4-8.el6_6.x86_64 already installed and latest version
Nothing to do
1.2、配置(以163郵箱為例)
首先你的郵箱要支持你的需求，到郵箱里去配置
然后到/etc/mail.rc的配置文件中去添加
set from=admin@163.com smtp=smtp.163.com smtp-auth-user=admin smtp-auth-password=xxxxxx smtp-auth=login
[root@linux-node2 ~]# echo “12345” | mail -v -s “test” admin@163.com
至此應該是沒問題，但是就是收不到郵件。得了，開始排錯！所有的網絡、配置檢查完成后，還是收不到郵件，最后檢查到端口發現問題！！！
[root@linux-node2 ~]# telnet smtp.163.com 25
Trying 220.181.12.17...
^C
[root@orcherstrator ~]# nc -vz -w 1 smtp.163.com 25
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
nc: connect to smtp.163.com port 25 (tcp) timed out: Operation now in progress
原來服務器根本就不能和第三方郵箱建立連接，問題找到，開始處理，一查才知道阿里云服務器把25端口給封了，需要申請解封。好吧！登錄管理控制臺，開始申請！！！
阿里云的審核速度還挺快的，兩個多小時后反饋結果了，不過看看就吐口老血！！！
只能想其他的辦法唄！！最后決定使用163郵箱的465加密端口
[root@orcherstrator ~]# telnet smtp.163.com 465
Trying 220.181.12.14...
Connected to smtp.163.com.
Escape character is '^]'.
^C
Connection closed by foreign host.
root@orcherstrator ~]# nc -vz -w 1 smtp.163.com 465
Connection to smtp.163.com 465 port [tcp/urd] succeeded!
看樣子有戲哦！！！修改/etc/mail.rc的配置
set from=admin@163.com
set smtp="smtps://smtp.163.com:465"
set smtp-auth-user=admin@163.com
set smtp-auth-password=xxxxx
set smtp-auth=login
set smtp-use-starttls
set ssl-verify=ignore
set nss-config-dir=/etc/pki/nssdb/
[root@linux-node2 ~]# echo 'hello' |mail -v -s "test" yueyuancun@163.com
Resolving host smtp.163.com . . . done.
Connecting to 123.125.50.133 . . . connected.
Error in certificate: Peer's certificate issuer is not recognized. ##沒有對端的證書
Comparing DNS name: "*.163.com"
SSL parameters: cipher=AES-128-GCM, keysize=128, secretkeysize=128,
issuer=CN=GeoTrust SSL CA - G3,O=GeoTrust Inc.,C=US
subject=CN=*.163.com,O="NetEase (Hangzhou) Network Co., Ltd",L=HangZhou,ST=ZheJiang,C=CN
220 163.com Anti-spam GT for Coremail System (163com[20141201])
>>> EHLO linux-node2
250-mail
250-PIPELINING
250-AUTH LOGIN PLAIN
250-AUTH=LOGIN PLAIN
250-coremail 1Uxr2xKj7kG0xkI17xGrU7I0s8FY2U3Uj8Cz28x1UUUUU7Ic2I0Y2UFVHs-cUCa0xDrUUUUj
250-STARTTLS
250 8BITMIME
>>> AUTH LOGIN
334 dXNlcm5hbWU6
>>> eXVleXVhbmN1bkAxNjMuY29t
334 UGFzc3dvcmQ6
>>> aGVsbG9uaWhhbzE5ODkxMA==
535 Error: authentication failed
smtp-server: 535 Error: authentication failed
"/root/dead.letter" 11/299
. . . message not sent. ##郵件沒有發出去
至此，網上的case都說能收到郵件，但是我這就是收不到，那就根據錯誤來解決唄！！！搞證書
[root@linux-node2 ~]# mkdir -p /root/.certs/
[root@linux-node2 ~]# echo -n | openssl s_client -connect smtp.163.com:465 | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > ~/.certs/163.crt
depth=2 C = US, O = GeoTrust Inc., CN = GeoTrust Global CA
verify return:1
depth=1 C = US, O = GeoTrust Inc., CN = GeoTrust SSL CA - G3
verify return:1
depth=0 C = CN, ST = ZheJiang, L = HangZhou, O = "NetEase (Hangzhou) Network Co., Ltd", CN = *.163.com
verify return:1
DONE
[root@linux-node2 ~]# certutil -A -n "GeoTrust SSL CA" -t "C,," -d ~/.certs -i ~/.certs/163.crt
[root@linux-node2 ~]# certutil -A -n "GeoTrust Global CA" -t "C,," -d ~/.certs -i ~/.certs/163.crt
[root@linux-node2 ~]# certutil -L -d /root/.certs
Certificate Nickname Trust Attributes
SSL,S/MIME,JAR/XPI
GeoTrust SSL CA C,,
[root@linux-node2 ~]# cd /root/.certs/
[root@linux-node2 .certs]# certutil -A -n "GeoTrust SSL CA - G3" -t "Pu,Pu,Pu" -d ./ -i 163.crt
Notice: Trust flag u is set automatically if the private key is present.
[root@linux-node2 .certs]# cd
[root@linux-node2 ~]# vim /etc/mail.rc
set from=admin@163.com
set smtp="smtps://smtp.163.com:465"
set smtp-auth-user=admin@163.com
set smtp-auth-password=xxxxx
set smtp-auth=login
set smtp-use-starttls
set ssl-verify=ignore
set nss-config-dir=/root/.certs
[root@linux-node2 ~]# echo 'hello' |mail -v -s "test" admin@163.com
Resolving host smtp.163.com . . . done.
Connecting to 123.125.50.132 . . . connected.
Comparing DNS name: "*.163.com"
SSL parameters: cipher=AES-128-GCM, keysize=128, secretkeysize=128,
issuer=CN=GeoTrust SSL CA - G3,O=GeoTrust Inc.,C=US
subject=CN=*.163.com,O="NetEase (Hangzhou) Network Co., Ltd",L=HangZhou,ST=ZheJiang,C=CN
220 163.com Anti-spam GT for Coremail System (163com[20141201])
>>> EHLO linux-node2
250-mail
250-PIPELINING
250-AUTH LOGIN PLAIN
250-AUTH=LOGIN PLAIN
250-coremail 1Uxr2xKj7kG0xkI17xGrU7I0s8FY2U3Uj8Cz28x1UUUUU7Ic2I0Y2UF6b612UCa0xDrUUUUj
250-STARTTLS
250 8BITMIME
>>> AUTH LOGIN
334 dXNlcm5hbWU6
>>> eXVleXVhbmN1bkAxNjMuY29t
334 UGFzc3dvcmQ6
>>> aGVsbG9uaWhhbzE5ODk=
235 Authentication successful
>>> MAIL FROM:<admin@163.com>
250 Mail OK
>>> RCPT TO:<admin@163.com>
250 Mail OK
>>> DATA
354 End data with <CR><LF>.<CR><LF>
>>> .
250 Mail OK queued as smtp2,DNGowADH53eJp5BbGYUHAA--.2S2 1536206732
>>> QUIT
221 Bye
終于成功了！！！！
注:不管能否解決你遇到的問題，歡迎相互交流，共同提高！
