install_tools() {
#下载常用软件和工具包
yum install epel-release -y
yum update -y
yum install -y lrzsz nmap tree dos2unix nc telnet wget git htop net-tools gcc gcc-c++ vim telnet zip unzip iotop iftop screen lsof
}
set_epel() {
#配置epel源
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup &&\
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
yum makecache
}
mkdir_directory() {
#创建目录
[ ! -d /data/tools ] && mkdir -p /data/tools
[ ! -d /application ] && mkdir -p /application
[ ! -d /data/package ] && mkdir -p /data/package
[ ! -d /data/backup ] && mkdir -p /data/backup
[ ! -d /data/scripts ] && mkdir -p /data/scripts
}
set_ssh() {
#备份sshd配置文件
cp /etc/ssh/sshd_config{,.bak}
#是否授权root登陆
sed -e 's/\#PermitRootLogin no/PermitRootLogin yes/' -i /etc/ssh/sshd_config > /dev/null 2>&1
#禁止空密码登陆
sed -e 's/\#PermitEmptyPasswords yes/PermitEmptyPasswords no/' -i /etc/ssh/sshd_config > /dev/null 2>&1
#禁止使用密码登陆
sed -e 's/\#PasswordAuthentication no/PermitEmptyPasswords yes/' -i /etc/ssh/sshd_config > /dev/null 2>&1
sed -e 's/GSSAPIAuthentication yes/GSSAPIAuthentication no/' -i /etc/ssh/sshd_config > /dev/null 2>&1
sed -e 's/#UseDNS yes/UseDNS no/' -i /etc/ssh/sshd_config > /dev/null 2>&1
#修改ssh默认连接端口
#sed -e 's/#Port 22/Port 22222/' -i /etc/ssh/sshd_config > /dev/null 2>&1
sed -i '/StrictHostKeyChecking/ s/ask/no/' /etc/ssh/ssh_config > /dev/null 2>&1
sed -i '/StrictHostKeyChecking/ s/^#/^/' /etc/ssh/ssh_config > /dev/null 2>&1
sed -i '/StrictHostKeyChecking/a UserKnownHostsFile \/dev\/null' /etc/ssh/ssh_config > /dev/null 2>&1
sed -i 's/GSSAPIAuthentication yes/GSSAPIAuthentication no/' /etc/ssh/ssh_config > /dev/null 2>&1
#重启ssh服务
systemctl restart sshd > /dev/null 2>&1
}
time_sync() {
#时区修改与时间同步
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
# /usr/sbin/ntpdate ntp1.aliyun.com;/sbin/hwclock -w"
# echo "00 * * * * /usr/sbin/ntpdate ntp1.aliyun.com;/sbin/hwclock -w" >>/var/spool/cron/root
# chmod 600 /var/spool/cron/root
echo "00 01 * * * /usr/sbin/ntpdate time.nist.gov >/dev/null 2>&1" >> /var/spool/cron/root
[ `grep ntpdate /var/spool/cron/root |wc -l` -ne 0 ] && action "uptime set" /bin/true || action "uptime set" /bin/false
}
closed_selinux() {
#关闭selinux
sed -i 's#=enforcing#=disabled#g' /etc/selinux/config
setenforce 0
getenforce
}
closed_iptables() {
#closed firewalld.service
systemctl stop firewalld.service
systemctl disable firewalld.service
}
closed_postfinx() {
#关闭邮件服务
systemctl stop postfix.service
systemctl disable postfix.service
}
set_limits() {
#nofile limits
echo " * soft nofile 65535" >> /etc/security/limits.conf
echo " * hard nofile 65535" >> /etc/security/limits.conf
echo " * soft nproc 102400" >> /etc/security/limits.conf
echo " * hard nproc 102400" >> /etc/security/limits.conf
echo " * soft memlock unlimited" >> /etc/security/limits.conf
echo " * hard memlock unlimited" >> /etc/security/limits.conf
ulimit -SHn 65535
}
set_utf8() {
#更改字符集
/bin/cp /etc/sysconfig/i18n /etc/sysconfig/i18n.bak
echo 'LANG="en_US.UTF-8"' >/etc/sysconfig/i18n
}
time_out() {
##时间超时 历史纪录
echo 'export TMOUT=600' >> /etc/rc.local
echo 'export HISTSIZE=50' >> /etc/rc.local
echo 'export HISTFILESIZE=50' >> /etc/rc.local
}
lock_file() {
#锁定关键系统文件
chattr +ai /etc/passwd
chattr +ai /etc/shadow
chattr +ai /etc/group
chattr +ai /etc/gshadow
chattr +ai /etc/inittab
}
clean_issue() {
#清空/etc/issue，去除系统及内核版本登陆前的屏幕显示
/bin/cp /etc/issue /etc/issue.bak
>/etc/issue
[ `cat /etc/issue|wc -l` -eq 0 ] && action "/etc/issue set" /bin/true || action "/etc/issue set" /bin/false
}
optimize_kernel() {
cat >>/etc/sysctl.conf<<EOF
#禁止ping
net.ipv4.icmp_echo_ignore_all=1
#表示开启SYN Cookies。当出现SYN等待队列溢出时，启用cookies来处理，可防范少量SYN攻击，默认为0，表示关闭；
net.ipv4.tcp_syncookies = 1
#表示开启重用。允许将TIME-WAIT sockets重新用于新的TCP连接，默认为0，表示关闭；
net.ipv4.tcp_tw_reuse = 1
#表示开启TCP连接中TIME-WAIT sockets的快速回收，默认为0，表示关闭；
net.ipv4.tcp_tw_recycle = 1
#修改系統默认的 TIMEOUT 时间
net.ipv4.tcp_fin_timeout
#表示当keepalive起用的时候，TCP发送keepalive消息的频度。缺省是2小时，改为20分钟。
net.ipv4.tcp_keepalive_time = 1200
#表示用于向外连接的端口范围。缺省情况下很小：32768到61000，改为10000到65000。（注意：这里不要将最低值设的太低，否则可能会占用掉正常的端口！）
net.ipv4.ip_local_port_range = 10000 65000
#表示SYN队列的长度，默认为1024，加大队列长度为8192，可以容纳更多等待连接的网络连接数。
net.ipv4.tcp_max_syn_backlog = 8192
#表示系统同时保持TIME_WAIT的最大数量，如果超过这个数字，TIME_WAIT将立刻被清除并打印警告信息。默 认为180000，改为5000。对于Apache、Nginx等服务器，上几行的参数可以很好地减少TIME_WAIT套接字数量，但是对于 Squid，效果却不大。此项参数可以控制TIME_WAIT的最大数量，避免Squid服务器被大量的TIME_WAIT拖死。
net.ipv4.tcp_max_tw_buckets = 5000
EOF
}
