1.安装mailx

yum install mailx -y

2.配置证书

mkdir -p /root/.certs
echo -n | openssl s_client -connect smtp.qq.com:465 | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > ~/.certs/qq.crt
certutil -A -n "GeoTrust SSL CA" -t "C,," -d ~/.certs -i ~/.certs/qq.crt
certutil -A -n "GeoTrust Global CA" -t "C,," -d ~/.certs -i ~/.certs/qq.crt
certutil -L -d /root/.certs
cd /root/.certs
certutil -A -n "GeoTrust SSL CA - G3" -t "Pu,Pu,Pu" -d ./ -i qq.crt

3.修改mailx配置文件

vim /etc/mail.rc

在文件末尾添加：

set bsdcompat
set sendcharsets=iso-8859-1,utf-8
set [email protected]
set smtp=smtps://smtp.qq.com:465
set [email protected]
set smtp-auth-password=ABC123
set smtp-auth=login
set ssl-verify=ignore
set nss-config-dir=/root/.certs

PS:这里配的是QQ邮箱，其中smtp-auth-password是授权码不是密码。

怎么拿授权码：

4.发送邮件测试

echo "this is a prisoner break "|mail -s "test" [email protected]

5.实践：

本机安装了denghosts,为了能看到相关的统计信息，每天发一封邮件到我的邮箱

[root@teddylu1987 .certs]# list=$(sed -n /^sshd/p /etc/hosts.deny)
[root@teddylu1987 .certs]# list2=$(sed -n /^sshd/p /etc/hosts.deny|wc -l)
[root@teddylu1987 .certs]# list3=$(cat /etc/hosts.deny)
[root@teddylu1987 .certs]# echo -e "$list"|mail -s "linode-denyhosts-status" [email protected]
[root@teddylu1987 .certs]# echo -e "$list2"|mail -s "linode-denyhosts-status" [email protected]
[root@teddylu1987 .certs]# echo -e "$list3"|mail -s "linode-denyhosts-status" [email protected]

[root@teddylu1987 shell]# cat denyhosts.sh
#!/bin/bash
RETVAL=0
FAILCOUNT=0
SCRIPT_PATH="/home/crontab"
MAIL_GROUP="[email protected] [email protected] [email protected]"

list1=$(sed -n /^sshd/p /etc/hosts.deny)
list2=$(sed -n /^sshd/p /etc/hosts.deny|wc -l)
list3=$(cat /etc/hosts.deny)

echo -e "$list1"|mail -s "linode-denyhosts-status-about-denyhosts" ${MAIL_GROUP}
echo -e "$list2"|mail -s "linode-denyhosts-status-about-numbers" ${MAIL_GROUP}



crontab -l

#check denyhosts status everynight 9:30pm
30 21 * * * /bin/sh /backup/shell/denyhosts.sh >/dev/null 2 >&1