Centos 7.9 优化脚本

修改网卡

vim /etc/sysconfig/grub

# 为GRUB_CMDLINE_LINUX变量增加两个参数 net.ifnames=0 biosdevname=0
GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=centos/root rd.lvm.lv=centos/swap net.ifnames=0 biosdevname=0 rhgb quiet"

# 重新生成grub配置文件
grub2-mkconfig -o /boot/grub2/grub.cfg

# 修改网卡配置文件
mv /etc/sysconfig/network-scripts/ifcfg-ens192 /etc/sysconfig/network-scripts/ifcfg-eth0

vim /etc/sysconfig/network-scripts/ifcfg-eth0

# 修改如下内容
NAME=eth0
DEVICE=eth0

systemctl restart network.service

reboot now

综合脚本

#!/usr/bin/env bash

. /etc/rc.d/init.d/functions
export LANG=zh_CN.UTF-8

if [ "$(uname -i)" != "x86_64" ]; then
  echo "this script is only for 64bit Operating System !"
  exit 1
fi
echo "the platform is ok"

set -ex

#一级菜单
menu1() {
  clear
  cat <<EOF
----------------------------------------
|****    欢迎使用centos7.9优化脚本    ****|
----------------------------------------
1. 一键优化
2. 自定义优化
3. 退出
EOF
  read -r -p "Please enter your choice[1-3]: " num1
}

#二级菜单
menu2() {
  clear
  cat <<EOF
--------------------------------------------
|**** Please enter your choice: [1-13] ****|
--------------------------------------------
1. 修改字符集
2. 关闭selinux
3. 关闭firewalld
4. 精简开机启动
5. 修改文件描述符
6. 安装常用工具
7. 优化系统内核
8. 加快ssh登录速度
9. 禁用ctrl+alt+del重启
10.设置时间同步
11.history优化
12.返回上级菜单
13.退出
EOF
  read -r -p "Please enter your choice[1-13]: " num2
}

#1.修改字符集
locale_set() {
  echo "========================修改字符集=========================="
  cat >/etc/locale.conf <<EOF
LANG="zh_CN.UTF-8"
#LANG="en_US.UTF-8"
SYSFONT="latarcyrheb-sun16"
EOF
  . /etc/locale.conf
  cat /etc/locale.conf
  echo 'stty erase ^H' >>/etc/profile
  echo "syntax on" >>/root/.vimrc
  echo "==========================================================="
  sleep 2
}

#2.关闭selinux
selinux_set() {
  echo "========================禁用SELINUX========================"
  if [ "$(grep -c "SELINUX=disabled" /etc/sysconfig/selinux)" -eq 0 ]; then
    sed -i "s#SELINUX=enforcing#SELINUX=disabled#g" /etc/sysconfig/selinux
    setenforce 0
    grep SELINUX=disabled /etc/sysconfig/selinux
    getenforce
  else
    echo 'SELINUX已处于关闭状态'
    grep SELINUX=disabled /etc/sysconfig/selinux
    getenforce
  fi
  echo "==========================================================="
  sleep 2
}

#3.关闭firewalld
firewalld_set() {
  echo "=======================禁用firewalld========================"
  # 关闭IPv6
  cat >/etc/modprobe.d/ipv6.conf <<EOF
alias net-pf-10 off
options ipv6 disable=1
EOF
  echo "NETWORKING_IPV6=off" >>/etc/sysconfig/network
  iptables -F
  iptables -X
  iptables -Z
  systemctl stop firewalld.service
  systemctl disable firewalld.service
  systemctl list-unit-files | grep firewalld
  firewall-cmd --state
  echo "==========================================================="
  sleep 5
}

#4.精简开机启动
chk_set() {
  echo "========================精简开机启动========================="
  systemctl disable auditd.service
  systemctl disable postfix.service
  systemctl list-unit-files | grep -E "auditd|postfix"
  echo "==========================================================="
  sleep 2
}

#5.修改文件描述符
limit_set() {
  echo "=======================修改文件描述符========================"
  ulimit -SHn 65535
  cat /etc/security/limits.conf
  ulimit -Sn
  ulimit -Hn
  echo "==========================================================="
  sleep 2
}

#6.安装常用工具
yum_set() {
  echo "======================安装常用工具及========================="
  yum install -y net-tools vim tree htop iftop lsof tcpdump nethogs nfs-utils httpd-tools sysstat \
    iotop lrzsz sl wget unzip telnet nmap nc psmisc rsync bash-completion vim-enhanced \
    dos2unix bash-completion bash-completion-extra
  echo "==========================================================="
  sleep 2
}

#7. 优化系统内核
kernel_set() {
  echo "=======================优化系统内核=========================="
  if [ "$(grep -c conntrack /etc/sysctl.conf)" -eq 0 ]; then
    cat >>/etc/sysctl.conf <<EOF
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_fin_timeout = 2
net.ipv4.route.gc_timeout = 100
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.ip_local_port_range = 4000 65000
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.core.somaxconn = 16384
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.rmem_default = 8388608
net.core.wmem_default = 8388608
net.core.netdev_max_backlog = 262144
#net.netfilter.nf_conntrack_max = 25000000
#net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120
#net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
#net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
#net.netfilter.nf_conntrack_tcp_timeout_established = 180
EOF
    sysctl -p
  else
    echo "优化项已存在。"
  fi
  echo "==========================================================="
  sleep 2
}

#8.加快ssh登录速度
ssh_set() {
  echo "=======================加快ssh登录速度======================="
  sed -i 's#^GSSAPIAuthentication yes$#GSSAPIAuthentication no#g' /etc/ssh/sshd_config
  sed -i 's/#UseDNS yes/UseDNS no/g' /etc/ssh/sshd_config
  systemctl restart sshd.service
  grep GSSAPIAuthentication /etc/ssh/sshd_config
  grep UseDNS /etc/ssh/sshd_config
  echo "==========================================================="
  sleep 2
}

#9. 禁用ctrl+alt+del重启
restart_set() {
  echo "====================禁用ctrl+alt+del重启===================="
  rm -rf /usr/lib/systemd/system/ctrl-alt-del.target
  echo "==========================================================="
  sleep 2
}

#10. 设置时间同步
date_set() {
  echo "========================设置时间同步========================="
  yum install -y chrony
  systemctl enable chronyd.service
  sed -i "s!#local stratum 10!local stratum 10!g" /etc/chrony.conf
  timedatectl set-timezone Asia/Shanghai
  chronyc -a makestep
  echo "==========================================================="
  sleep 2
}

#11. history优化
history_set() {
  echo "========================history优化========================"
  if [ "$(grep -c HISTTIMEFORMAT /etc/profile)" -eq 0 ]; then
    cat >>/etc/profile <<EOF
#设置history格式
export HISTTIMEFORMAT="[%Y-%m-%d %H:%M:%S] [$(whoami)] [$(who am i | awk '{print $NF}' | sed -r 's#[()]##g')]: "
#记录shell执行的每一条命令
export PROMPT_COMMAND='\
if [ -z "$OLD_PWD" ];then
    export OLD_PWD=$PWD;
fi;
if [ ! -z "$LAST_CMD" ] && [ "$(history 1)" != "$LAST_CMD" ]; then
    logger -t $(whoami)_shell_dir "[$OLD_PWD]$(history 1)";
fi;
export LAST_CMD="$(history 1)";
export OLD_PWD=$PWD;'
EOF
    source /etc/profile
  else
    echo "优化项已存在。"
  fi
  echo "==========================================================="
  sleep 2
}

#控制函数
main() {
  menu1
  case $num1 in
  1)
    locale_set
    selinux_set
    firewalld_set
    chk_set
    limit_set
    yum_set
    kernel_set
    ssh_set
    restart_set
    date_set
    history_set
    ;;
  2)
    menu2
    case $num2 in
    1)
      locale_set
      ;;
    2)
      selinux_set
      ;;
    3)
      firewalld_set
      ;;
    4)
      chk_set
      ;;
    5)
      limit_set
      ;;
    6)
      yum_set
      ;;
    7)
      kernel_set
      ;;
    8)
      ssh_set
      ;;
    9)
      restart_set
      ;;
    10)
      date_set
      ;;
    11)
      history_set
      ;;
    12)
      main
      ;;
    13)
      exit
      ;;
    *)
      echo 'Please select a number from [1-13].'
      ;;
    esac
    ;;
  3)
    exit
    ;;
  *)
    echo 'Err:Please select a number from [1-3].'
    sleep 3
    main
    ;;
  esac
}
main $*