[Linux]Linux 基础知识、常用命令和 Shell 脚本

一、Linux

1. Linux 的应用领域及介绍

2. 网络连接的三种方式

3. Linux 目录介绍

4. vi 和 vim

5. 开机、关机、登录、注销

6. 用户管理

7. 用户、组相关的配置文件

8. 运行级别

9. 帮助指令

10. 文件目录指令

11. 日期时间指令

12. 查找指令

13. 压缩和解压

14. 组管理

15. 权限管理

16. 定时任务调度 crond

17. 定时任务调度 at

18. 磁盘分区、挂载

19. 网络配置

20. 进程管理

21. 服务管理

22. rpm 和 yum

23. 搭建 JavaEE 环境

1. 安装配置 Oracle Java 8

2. 安装配置 tomcat8

3. 安装配置 MySQL5.7

24. Shell 编程

#!/bin/bash
# 定义变量A
A=100
echo A=$A
# 撤销定义变量A
unset A
echo A=$A
# 定义静态变量B，不可 unset
readonly B=200
echo B=$B

#!/bin/bash
# 依次输出每一个参数变量
echo args0=$0
echo args1=$1
echo args2=$2
# 整体输出所有参数
echo args=$*
# 区别输出所有参数
echo args_=$@
# 输出参数个数
echo args_nums=$#

# 分支格式
#!/bin/bash
if [ "ok" = "ok" ]
then 
    echo "equal"
elif[ "lcx" = "lcx" ]
    echo "not equal"
else
	echo "quit"
fi

# case 语句
#!/bin/bash
case $1 in
"1")
echo "Monday"
;;
"2")
echo "Tuesday"
;;
*)
echo "other"
;;
esac

# for 循环 1
#!/bin/bash
# $* 将命令行参数看作一个整体，所以 for 循环只执行一次
for i in "$*"
do
        echo "args is $i"
done
echo "==========="
# $@ 区别对待各个命令行参数，所以有几个参数 for 循环执行>几次
for j in "$@"
do
        echo "args is $j"
done

# for 循环 2
#!/bin/bash
SUM=0
for(( i=1; i<=$1; i++))
do
        SUM=$[ $SUM+$i ]
done
echo "sum = $SUM"

# while 循环
#!/bin/bash
SUM=0
i=0
while [ $i -le $1 ]
do
        SUM=$[$SUM+$i]
        i=$[ $i+1 ]
done
echo "The result is $SUM"

# read 读取输入
#!/bin/bash
# 读取控制台输入的一个值
read -p "Please input a number:" NUMBER
echo "The number that you entered is $NUMBER"
# 读取用户 10s 内输入的一个值
read -t 10 -p "Please input a number:" NUMBER1
echo "The number you entered is $NUMBER1"

#!/bin/bash
# Define the funtion
function getSum() {
        SUM=$[$n1+$n2]
        echo "Sum is $SUM"
}

read -p "Input the first number:" n1
read -p "Input the second number:" n2

# Call the function
getSum $n1 $n2

25. Shell 之定时备份数据库

# 每天凌晨 2:30 定时备份指定的数据库，同时检查 10 天前的备份文件是否存在，存在则删除
DIRECTORY=/data
DATETIME=$(date +%Y%m%d%H%M%S)
DB_HOST=localhost
DB_USER=root
DB_PWD=2020@mywife
DB_NAME=mine

# If the save directory not exists, then create it
[ ! -d "${DIRECTORY}/${DATETIME}" ] && mkdir -p "${DIRECTORY}/${DATETIME}"

# Backup the database
mysqldump -h${DB_HOST} -u${DB_USER} -p${DB_PWD} ${DB_NAME} > ${DIRECTORY}/${DATETIME}/${DB_NAME}.sql

# Compress the backup file
cd /${DIRECTORY}
tar -zcvf ${DIRECTORY}/${DATETIME}.tar.gz ${DATETIME}
rm -rf ${DIRECTORY}/${DATETIME}

# Delete the file that existing more than 10 days
find ${DIRECTORY} -atime +10 -name "*.tar.gz" -exec rm -rf {} \;
echo "Backup databse named ${DB_NAME} successfully"

# 定时调用脚本
crontab -e
30 2 * * * /home/bash/backup_mysql_mine.sh

26. apt 和 ssh 远程登录

deb http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse

27. 日志管理

28. 内核升级

29. Linux 系统备份与恢复

30. webmin 和 bt 运维工具