It relates to the content:
1.dns
2. Network yum source
3.epel source
4. Time synchronization
5. Installation Vim
6. The set the maximum number of open file descriptors
7. Disable SELinux
8. The closed firewall
9. Optimization ssh connection speed
10. The kernel parameters optimization
11. set vim backspace key to delete the last character type
12. update kernel
script as follows:
#!/bin/bash
#author yundd by
#this script is only for CentOS 7.x
#check the OS
platform=`uname -i`
if [ $platform != "x86_64" ];then
echo "this script is only for 64bit Operating System !"
exit 1
fi
echo "the platform is ok"
cat << EOF
your system is CentOS 7 x86_64
EOF
#添加公网DNS地址
cat >> /etc/resolv.conf << EOF
nameserver 114.114.114.114
EOF
#Yum源更换为国内阿里源
yum install wget telnet -y
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
#添加阿里的epel源
#add the epel
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
# rpm -ivh http://dl.Fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-8.noarch.rpm
#yum重新建立缓存
yum clean all
yum makecache
#同步时间
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
yum -y install ntp
/usr/sbin/ntpdate cn.pool.ntp.org
echo "* 4 * * * /usr/sbin/ntpdate cn.pool.ntp.org > /dev/null 2>&1" >> /var/spool/cron/root
systemctl restart crond.service
#安装vim
yum -y install vim
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
#安装lrzsz实现win与linux之间的文件互相下载上传
yum -y install lrzsz
#设置最大打开文件描述符数
echo "ulimit -SHn 102400" >> /etc/rc.local
cat >> /etc/security/limits.conf << EOF
* soft nofile 655350
* hard nofile 655350
EOF
#禁用selinux
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
setenforce 0
#关闭防火墙
systemctl disable firewalld.service
systemctl stop firewalld.service
#set ssh
sed -i 's/^GSSAPIAuthentication yes$/GSSAPIAuthentication no/' /etc/ssh/sshd_config
sed -i 's/#UseDNS yes/UseDNS no/' /etc/ssh/sshd_config
systemctl restart sshd.service
#内核参数优化
cat >> /etc/sysctl.conf << EOF
vm.overcommit_memory = 1
net.ipv4.ip_local_port_range = 1024 65536
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_syncookies=1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_fin_timeout=120
net.ipv4.tcp_keepalive_time = 2400
net.ipv4.tcp_max_syn_backlog = 8192
net.ipv4.tcp_max_tw_buckets = 5000
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_abort_on_overflow = 0
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.netdev_max_backlog = 262144
net.core.somaxconn = 262144
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_max_syn_backlog = 262144
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.ipv4.netfilter.ip_conntrack_max = 2097152
net.nf_conntrack_max = 655360
net.netfilter.nf_conntrack_tcp_timeout_established = 1200
EOF
/sbin/sysctl -p
#vim定义退格键可删除最后一个字符类型
echo 'alias vi=vim' >> /etc/profile
echo 'stty erase ^H' >> /etc/profile
cat >> /root/.vimrc << EOF
set tabstop=4
set shiftwidth=4
set expandtab
syntax on
"set number
EOF
# update soft
# yum -y update