网络配置

设置IP

略

ip_froward

查看 sysctl -a | grep ip_
修改 vi /etc/sysctl.conf

net.ipv4.ip_forward = 1

最大使用内存

vm.max_map_count=262144

生效 sysctl -p

系统更新

yum -y update

安装扩展及工具

yum -y install epel-release net-tools bind-utils telnet wget sysstat

文件链接限制

查看

ulimit -n

修改 vi /etc/security/limits.conf

* - nofile 65536
* soft nproc 65536
* hard nproc 65536
* soft nofile 65536
* hard nofile 65536

rm /etc/security/limits.d/*  -rf

安全

selinux

查看

getenforce

修改 临时 setenforce 0 永久 vi /etc/sysconfig/selinux

sed -i '/SELINUX/s/enforcing/disabled/' /etc/selinux/config

setenforce 0

设置 firewalld

设置 ssh

vi /etc/ssh/sshd_config

禁用root用户，密钥登陆 切换为其他用户登录

PermitRootLogin without-password
#PermitRootLogin yes

修改22端口

登陆加速

GSSAPIAuthentication no
UseDNS no

系统时间

ntp

yum install chrony
systemctl enable chronyd.service
systemctl start chronyd.service

建议使用 ntp

yum install ntp
systemctl start ntpd
systemctl enable ntpd

总归

#!/bin/bash

echo "===============更新系统 `date`"          
yum -y update
echo "===============安装拓展工具 `date`" 
yum -y install epel-release net-tools bind-utils
echo "===============修改文件连接数限制 `date`" 

cat >> /etc/security/limits.conf << EOF
* - nofile 65536
* soft nproc 65536
* hard nproc 65536
* soft nofile 65536
* hard nofile 65536
EOF

rm /etc/security/limits.d/*  -rf


echo "===============禁用selinux `date`" 

sed 's/SELINUX=/#SELINUX=/g'  /etc/selinux/config -i
echo "SELINUX=disabled" >> /etc/selinux/config

echo "===============禁用firewalld `date`"
systemctl disable firewalld

echo "===============安装ntp服务 `date`"

yum install ntp -y

systemctl enable ntpd 

echo "===============初始化系统完毕，重启系统后生效 `date`"