centos7常用操作总结(持续更新)

川长思鸟来 2022-12-29 14:00 164阅读 0赞

tcpdump -i eth0 icmp
    route -n
    route add default gw 192.168.16.1
    route del default gw 192.168.16.1
    route add default dev eth0
    
    systemctl is-enabled nginx是否开机启动nginx
    systemctl is-active mysql ngix是否启动
    systemctl start sendmail
    systemctl restart sendmail
    systemctl reload  sendmail
    systemctl stop sendmail
    systemctl enable  sendmail
    systemctl disable sendmail
    yum install sendmail -y
    systemctl list-units 查看运行的服务
    systemctl mask sendmail
    systemctl unmask sendmail
    
    cd /etc/yum.repos.d 
    mv CentOS-Base.repo CentOS-Base.repo.bak 
    
    
    #永久开发某个端口
    firewall-cmd --zone=public --add-port=22/tcp --permanent
    firewall-cmd --list-ports
    firewall-cmd --remove-port=80/tcp -permanent
    
    [openstack]
    name=openstack
    baseurl=http://mirrors.aliyun.com/centos/7/cloud/x86_64/openstack-train/
    failovermethod=priority
    enabled=1
    gpgcheck=0
    
    [Virt]
    name=virt
    baseurl=http://mirrors.aliyun.com/centos/7/virt/x86_64/kvm-common/
    enabled=1
    gpgcheck=0
    
    [libvirt]
    name=libvirt
    baseurl=http://mirrors.aliyun.com/centos/7/virt/x86_64/libvirt-latest/
    enabled=1
    gpgcheck=0
    
    
    [base]
    name=CentOS-$releasever - Base - mirrors.aliyun.com
    failovermethod=priority
    baseurl=http://mirrors.aliyun.com/centos/$releasever/os/$basearch/
            http://mirrors.aliyuncs.com/centos/$releasever/os/$basearch/
            http://mirrors.cloud.aliyuncs.com/centos/$releasever/os/$basearch/
    gpgcheck=1
    gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
    
    #released updates
    [updates]
    name=CentOS-$releasever - Updates - mirrors.aliyun.com
    failovermethod=priority
    baseurl=http://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
            http://mirrors.aliyuncs.com/centos/$releasever/updates/$basearch/
            http://mirrors.cloud.aliyuncs.com/centos/$releasever/updates/$basearch/
    gpgcheck=1
    gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
    
    #additional packages that may be useful
    [extras]
    name=CentOS-$releasever - Extras - mirrors.aliyun.com
    failovermethod=priority
    baseurl=http://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
            http://mirrors.aliyuncs.com/centos/$releasever/extras/$basearch/
            http://mirrors.cloud.aliyuncs.com/centos/$releasever/extras/$basearch/
    gpgcheck=1
    gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
    
    
    yum clean all
    yum makecache
    
    
    准备
    (1)环境准备
    systemctl stop firewalld.service #停止firewall
    systemctl disable firewalld.service #禁止firewall开机启动
    firewall-cmd --state #查看默认防火墙状态（关闭后显示notrunning，开启后显示running）
    vi /etc/selinux/config
    SELINUX=disabled
    关闭windows的防火墙
    sed -i 's/enforcing/disabled/' /etc/selinux/config
    setenforce 0
    swapoff -a
    sed -ri 's/.*swap.*/#&/' /etc/fstab
    free -g 验证 swap必须0
    
    
    hostnamectl set-hostname hadoop1
    vim /etc/hosts
    192.168.1.101 hadoop1
    
    yum install -y vim wget lsof tcpdump net-tools tree screen chrony
    
    vim /etc/chrony.conf
    yum install -y chrony
    server ntp1.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp2.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp3.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp4.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp5.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp6.aliyun.com iburst minpoll 4 maxpoll 10
    server ntp7.aliyun.com iburst minpoll 4 maxpoll 10
    
    systemctl restart chronyd.service
    systemctl status chronyd.service
    systemctl enable chronyd.service
    timedatectl set-timezone Asia/Shanghai
    chronyc sources
    timedatectl status
    
    vim /etc/resole.conf
    nameserver 192.168.1.1
    
    ip route
    
    (3)新建用户
    adduser hadoop
    passwd hadoop
    输入密码hadoop@123456
    vim /etc/sudoers
    ## Allow root to run any commands anywhere
    root    ALL=(ALL)       ALL
    hadoop  ALL=(ALL)       ALL
    admin   ALL=(ALL)       ALL
    
    (4)免密码登陆
    ssh key使用非对称加密生成公钥和私钥
    私钥放在~/.ssh目录
    公钥可以公开,放在~/.ssh/authorized_keys
    ssh-keygen -t rsa 
    输入密钥名称 回车
    输入密码     回车
    输入确认密码 回车 
    在所有机器上都运行之后
    ssh-copy-id hadoop1
    ssh-copy-id hadoop2
    ssh-copy-id hadoop3
    
    
    top查看3个指标 1,5,15分钟平均负载。cpu空闲比。空闲内存。
    shift+m 按照内存使用率进行排序
    shift+p 按照cpu使用率进行排序
    
    crontab -e //修改crontab,若文件不存在那么自动创建
    10  1 1 * * /data/backup/mysql.sh 每个月的第一天的1:10分运行
    0   1 * * * /data/backup/mysql.sh 每天1点执行
    */5 * * * * /data/backup/mysql.sh 每5分钟执行
    systemctl crond status
    systemctl crond start
    systemctl crond stop
    systemctl crond restart
    systemctl crond reload
    
    git安装
    wget https://github.com/git/git/archive/v2.24.0.tar.gz
    yum -y install curl-devel expat-devel gettext-devel openssl-devel zlib-devel gcc perl-ExtUtils-MakeMaker
    tar -zxvf v2.24.0.tar.gz
    cd git-2.24.0/
    make prefix=/usr/local/git all
    make prefix=/usr/local/git install
    vim /etc/profile
    export PATH=/usr/local/git/bin:$PATH
    source /etc/profile
    
    配置java环境
    JAVA_HOME=/developer/soft/jdk8
    JRE_HOME=$JAVA_HOME/jre
    CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
    PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
    export JAVA_HOME JRE_HOME CLASS_PATH PATH
    
    测试端口是否通
    telnet 118.25.11.236 80
    nc -zv 118.25.11.236 80
    netstat -an | grep ':7300'
    
    
    #10.0.0.2 网关地址
    ip route add default via 10.0.0.2
    ip route del default via 10.0.0.2
    #查看
    ip route show 
    #10.0.3.0这个网段从10.0.1.2默认网关出
    ip route add -net 10.0.3.0 netmask 255.255.255.0 via 10.0.1.2
    
    #查询安装过的包
    rpm -qa |grep "^zs"
    yum list installed | grep "^zs"
    #查看某个文件是哪个安装包产生的
    rpm -qf /etc/fstab
    #卸载
    yum -y remove 软件包
    
    yum install -y zip
    #将当前目录下所有的文件压缩成a.zip
    zip -r a.zip ./*
    #将a.zip解压缩到/root/b目录下
    unzip a.zip -d /root/b
    
    #将硬件时间设置为系统时间
    hwclock -s
    #将系统使时间设置为硬件时间
    hwclock -w 
    #在A服务器上操作，将B服务器上/home/lk/目录下所有的文件全部复制到本地的/root目录下
    scp -r root@192.168.1.16:/home/lk /root
    
    #在A服务器上将/root/lk目录下所有的文件传输到B的/home/lk/cpfile目录下
    scp -r /root/lk root@192.168.1.16:/home/lk/cpfile
    
    NetFilter是linux操作系统核心层内一个数据包处理模块。处在IP层挂载5个(preRouting,Input,OUTPUT,FORWARD,POST_ROUTING),iptables(tcp/udp模块)调用netfilter,
    iptables -nL
    
    yum install iptables-services;
    systemctl enable iptables;
    systemctl status iptables;
    
    vim /data/script/firewall.sh
    #!/bin/sh
    iptables -F
    list=/data/script/blacklist.txt
    for line in  `cat $list`; do
    	iptables -I INPUT -s$line -j DROP
    	echo "$line is dropped into blacklist"
    done
    crontab -e 
    * * * * * source /etc/profile; sh /data/script/firewall.sh
    systemctl restart crond
    
    数据包访问控制：ACCEPT, DROP,REJECT
    #访问本机80-100端口开放
    iptables -I INPUT -p tcp --dport 80:100 -j ACCEPT
    #访问本机22端口开放
    iptables -I INPUT -p tcp --dport 22 -J ACCEPT
    ipatbles -D INPUT -p tcp --dport 80 -j ACCEPT
    #nmap使用
    yum install nmap -y
    yum install nc -y
    nmap -sS -p 0-1000 192.168.16.139
    
    #查看来自10.10.163.232的并发访问
    netstat -an | grep 80 | grep 10.10.163.232 | grep EST -c