Linux 常用命令整理

1

1防火墙
  #el7
systemctl enable firewalld.service
systemctl disable firewalld.service
systemctl stop firewalld.service
systemctl start firewalld.service

2.selinux
setenforece 0
sed -i s/^SELINUX=.*/SELINUX=disabled/ /etc/sysconfig/selinux

2

1.配置本地yum源
mount -t iso9660 /dev/cdrom /media
zip -r /etc/yum.repos.d.zip /etc/yum.repos.d
rm /etc/yum.repos.d/* -rf
cat >/etc/yum.repos.d/CentOS-Media.repo <<'EOF'
[c7-media]
name=CentOS-7-local
baseurl=file:///media/
gpgcheck=0
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
EOF
yum clean all
yum makecache

2.配置163镜像源
cp -r /etc/yum.repos.d /etc/yum.repos.d.org
rm -rf /etc/yum.repos.d/*

cd /etc/yum.repos.d
wget http://mirrors.163.com/.help/CentOS6-Base-163.repo
#wget http://mirrors.163.com/.help/CentOS7-Base-163.repo
yum clean all
yum makecache

3.安装图形化界面
el6
yum -y groupinstall Desktop "X Window System" 
yum -y groupinstall chinese-support            --安装中文包 按需

yum groupremove “X 窗口系统”    --移除
el7
yum groupinstall "GNOME Desktop" "Graphical Administration Tools"    #centos7
ln -sf /lib/systemd/system/runlevel5.target /etc/systemd/system/default.target
reboot

4.el7安装vnc
yum install -y vnc-server
cp /lib/systemd/system/vncserver@.service  /etc/systemd/system/vncserver@:1.service
sed -i "s#<USER>#root#" /etc/systemd/system/vncserver@:1.service
sed -i "s#ExecStart=/usr/sbin#ExecStart=/sbin#" /etc/systemd/system/vncserver@:1.service
sed -i "s#PIDFile=/home/#PIDFile=/#" /etc/systemd/system/vncserver@:1.service
systemctl daemon-reload
vncpasswd
firewall-cmd --permanent --add-service vnc-server

systemctl restart firewalld.service
systemctl enable vncserver@:1.service
systemctl disable vncserver@:1.service
systemctl start vncserver@:1.service
systemctl stop vncserver@:1.service

5.el7配置ssh互信
ssh-keygen 
ssh-copy-id -i .ssh/id_rsa.pub user@host    

6.el7添加swap
[root@oracle ~]# dd if=/dev/zero of=/swapfile bs=1024 count=4194304
[root@oracle ~]# mkswap /swapfile
[root@oracle ~]# swapon /swapfile
[root@oracle ~]# echo "/swapfile none swap sw 0 0" >>/etc/fstab
[root@oracle ~]# free -m


7.修改默认启动级别
CentOS6
在CentOS6中可以使用以下命令修改对应的启动级别：
vi /etc/inittab
id:3:initdefault:           
　　
CentOS7
但是CentOS7中，在inittab设置不再生效
查看当前的默认target输入命令：
# systemctl get-default
　　
查看运行级别与target的对应关系可以执行以下命令：
ll /lib/systemd/system/runlevel*.target
其中multi-user.target 类似与之前的runlevel 3，graphical.target 类似与之前的runlevel 5。
修改为命令模式multi-user.target：
# systemctl set-default multi-user.target



8.格式化磁盘
echo -e "n
p



w
" |fdisk /dev/sdc > /dev/null   2>&1
mkfs -t ext4 -d /dev/sdc1
#mkfs.ext4 /dev/xvdc1
mount /dev/sdc1 /data
echo "/dev/sdc1 /data ext4 defaults 0 0" >>/etc/fstab