CentOS7 最小化安装.也有近1个 G...830M
ifconfig 已经过时了。
改用“ip addr”和“ip link”命令来查找网卡详情。
要知道统计数据，可以使用“ip -s link”。
network is not running after installation ...
vi /etc/sysconfig/network-scripts/ifcfg-eth0s3
### edit=> ONBOOT="yes"
systemctl restart network
bash:Bourne Again Shell（/bin/bash）
默认 Shell
```# 注释```
单行注释的写法
```echo $SHELL ```
当前 SHELL 的名称,例如:/bin/bash
```find / -name hell*```
从根目录开始,递归子目录,查找文件 hell*.*
软件包管理:
apt-get:Ubuntu.软件包管理工具
brew:macOS.apt-get...
yum:RedHat.apt-get...
yum -y install net-tools
yum -y install docker
yum -y install go
systemctl 是系统服务管理器命令，它实际上将 service 和 chkconfig 这两个命令组合到一起。
任务 旧指令 新指令
使某服务自动启动 chkconfig –level 3 httpd on systemctl enable httpd.service
使某服务不自动启动 chkconfig –level 3 httpd off systemctl disable httpd.service
检查服务状态 service httpd status systemctl status httpd.service （服务详细信息） systemctl is-active httpd.service （仅显示是否 Active)
显示所有已启动的服务 chkconfig –list systemctl list-units –type=service
启动某服务 service httpd start systemctl start httpd.service
停止某服务 service httpd stop systemctl stop httpd.service
重启某服务 service httpd restart systemctl restart httpd.service
//centos 查看所有运行中的服务的详细信息命令:
netstat -tunpl
ps -aux | grep YourKeyWordToSearch
Q:how to know OS Name?
lsb_release -a
cat /etc/os-release
cat /etc/redhat-release
Q:How to show disk space?
A:```df``` NOT ```dd```.
Q:df only show one disk. how to show another bigger disk?
A:```fdisk -l```
Q:如何限制一个命令执行的时间?
```timeout 1s ls```
SSH.DSA
---
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
dsa is not supported by default.
To compatible dsa, you need to add below line:
```PubkeyAcceptedKeyTypes +ssh-dss```
into your ~/.ssh/config
cat ~/.ssh/config
PubkeyAcceptedKeyTypes +ssh-dss
DNS:
---
//to set dns:
sudo su -
nmcli con mod enp4s0 ipv4.dns "202.99.192.66 202.99.192.68 8.8.4.4 8.8.8.8"
nmcli con up enp4s0
nmcli dev show enp4s0
# 在shell 中,将某个文件复制成一百个文件
for (( i=1; i<=100; i++ ))
do
cp bg.jpg bg$i.jpg
done
