centos7的基础优化你都做了吗？

#!/bin/sh
#因为现在大多都用的是centos7了所以6就没怎么写
#其它系统脑补
#优化命令提示符PS1，添加颜色
release=`cat /etc/redhat-release | awk -F'[ |.]' '{print $4}'`
echo "PS1='[[e[32;1m]u[e[0m]@[e[33;1m]h[e[0m] [e[34;1m]W[e[0m]]$ '" >>/etc/bashrc

#优化yum下载源

if [ `cat /etc/redhat-release | awk '{print $1}'` == 'CentOS' ];then
    curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
    curl -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
        sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
    yum makecache
else
    echo '这不是CentOS添加其它系统的软件仓库' && exit 1
fi
#安装常用工具软件
yum install -y  vim tree nc nmap dos2unix  wget lrzsz bash-completion net-tools
#关闭seLinux
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/selinux/config
#关闭并且禁用firewalld 或者iptables
if [ $release == 7 ];then
    systemctl stop  firewalld
    systemctl disable  firewalld
elif [ $release == 6 ];then
    sevice iptables stop
    chkconfig iptables off
fi
#设置时区
if [ $release == 7 ];then
    timedatectl set-timezone Asia/Shanghai
elif [ $release == 6 ];then
    echo '手动修改/etc/sysconfig/clock'
fi
#安装时间服务
if [ $release == 7 ];then
    yum install -y chrony && systemctl start chronyd
    timedatectl set-ntp 1 && timedatectl status
elif [ $release == 6 ];then
    yum install -y ntp
    service ntpd start
    chkconfig ntpd on
else
    echo "不存的版本，退出" && exit 3
fi
read -p "输入你的主机名称:" name
echo "你的主机名称是 $name"
if [ $release == 7 ];then
    hostnamectl set-hostname $name
elif [ $release == 6 ];then
    echo "HOSTNAME=$name" >>  /etc/sysconfig/network
    
fi

grep 'GSSAPIAuthentication' /etc/ssh/sshd_config
if [ `echo $?` == 0 ];then
sed -i 's@GSSAPIAuthentication yes@GSSAPIAuthentication no@g' /etc/ssh/sshd_config
fi
sed -i 's@UseDNS yes@UseDNS no@g' /etc/ssh/sshd_config
if [ `echo $?` != 0 ];then
sed -i 's@#UseDNS yes@UseDNS no@g' /etc/ssh/sshd_config
fi