SHELL部分复习/练习题相关总结

修改Apache服务器端口

编写脚本,实现对于Apache服务器的端口修改,默认需要输入端口号.请视作Selinux未开启

  #########################
  # Author:		NeuWings
  # Create_Time:	2021/03/05
  #########################
  #!/bin/bash
  
  [ -z "$*" ] && {
    echo Please input port number following script!
    exit
  }
  
  rpm -q http &> /dev/null ||{
    echo "Error: Apache is not installed!! "
    exit
  }
  
  netstat -antlupe | grep -E "\<$*\>" &> /dev/null && {
    echo "Error:Port $1 is used now"
    exit
  }
  
  
  sed "/^Listen/c Listen $1" -i /etc/httpd/conf/httpd.conf
  
  systemctl restart httpd &> /dev/null && {
    echo "Configure Port Successful."
  } || {
    echo "Something Error!"
  }

清除日志文件

编写脚本,实现对系统中Message日志文件的清理.

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

[ `"whoami"` = "root" ] || {
	echo "Error: This Script Must Run By Root!"
  exit
}

[ -e "/var/log/messages" ] || {
	echo "Messages File is not exist"
	exit
}

 > /var/log/messages || {
 echo "Uknown Error"
}

echo "Logs Cleaned UP"
exit

检查指定用户是否存在

检查指定用户是否存在.

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

[ -z "$*" ] && {
  echo 参数错误,请检查输入
  exit
}

id $1 &> /dev/null || {
  echo $1 is not exist.
  exit
}

echo $1 is exist

查看网卡设备的IP地址

检测输出本机中指定网卡设备的IP地址

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

[ -z "$*" ] && {
  echo Please Input Device Name!
  exit
}

ifconfig $* | awk -F " "  '$1~/inet\>/{print $2}'

统计系统中家目录不在Home目录下,但能够su切换用户的用户数量

编写脚本,输出系统中家目录不在Home目录下,但能够su切换用户的用户数量.

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

awk -F : 'BEGIN{n=0} $6!~/^\/home/&&/\<bash$|\<sh$|\<tcsh$/{print $0;n++} END{print n}' /etc/passwd

格式化输出信息

编写脚本,格式化输出指定网卡设备的IP地址,本机的主机名,当前登录用户的用户名.

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

[ -z "$*" ] && {
  echo Please Input Device Name!
  exit
}

echo "hostname:   `hostname`"

ifconfig $* | awk -F " "  '/inet\>/{print "ipaddress:  "$2}'

echo "USERNAME:   `whoami`"

根据文件内容批量创建用户

已知存在一个文件Userlist,格式内容如下,请根据该文件中的信息在系统中创建对应的用户.

##文件内容
user1 123
user2 223
user3 323

#########################
# Author:		NeuWings
# Create_Time:	2021/03/05
#########################
#!/bin/bash

[ `"whoami"` = "root" ] || {
  echo "Error: This Script Must Run By Root!"
  exit
}

[ -z "$*" ] && {
  echo Please Input Userlist File!
  exit
}

[ -e "$*" ] || {
  echo Userlist File Is Not Exist!
  exit
}

LINE=`awk 'BEGIN{n=0}{n++}END{print n}' $*`

for NUM in `seq 1 $LINE`
do
        echo '----------Create User----------'
        USERNAME=`awk "NR==$NUM"'{print $1}' $*`
        PASSWORD=`awk "NR==$NUM"'{print $2}' $*`
        id $USERNAME &> /dev/null && {
          echo $USERNAME is exist!
        } || {
          useradd $USERNAME
          echo $PASSWORD | passwd --stdin $USERNAME
          echo "$USERNAME Create success";
          echo "USERNAME set PASSWORD success"
        }
done

检查同网段IP为10-20的主机中能够Ping通的主机并输出可连通的主机的IP列表

#################################
# Author:         NeuWings
# Create_Time:    2021/03/09
#################################
#!/bin/bash

> check_host.list

for IP in {10..20}
do

     ping -w1 -c1 172.25.254.$IP &>/dev/null && {
       echo 172.25.254.$IP
       echo 172.25.254.$IP >> check_host.list
    }

done

设置时长为1分5秒的计时器

#################################
# Author:         NeuWings
# Create_Time:    2021/03/09
#################################
#!/bin/bash

#!/bin/bash
MIN=1
SEC=5

PRINT() {
  echo -n "After $1:$2 is end."
  echo -ne "\r"
  sleep 1
}

for ((;SEC>=0;SEC--))
do
        if [ "$SEC" = "0" -a "$MIN" = "0" ]
        then
          echo "Bye.                              "
        elif [ "$SEC" = "0" -a "$MIN" -gt "0" ]
        then
          PRINT $MIN $SEC
          SEC=59
          ((MIN--))
        fi
          PRINT $MIN $SEC
done

查询同IP段10-20的主机,输出可以连通的主机的IP地址以及主机名

#################################
# Author:			NeuWings
# Create_Time:		2021/03/09
#################################
#!/bin/bash

SSH()
{
/usr/bin/expect << EOF
set timeout 5
spawn ssh root@$1 hostname
expect {
	"yes/no" { send "yes\r";exp_continue }
	"password:" { send "$2\r" }
}
expect eof
EOF
}

> host_list

for IP in {10..20}
do
         ping -c1 -w1 172.25.254.$IP &> /dev/null && {
				 	SSH 172.25.254.$IP westos &> /dev/null && {
          HOSTNAME=`SSH 172.25.254.$IP westos | tail -n 1`
					echo "172.25.254.$IP $HOSTNAME"
          echo "172.25.254.$IP $HOSTNAME" >> host_list
					}
         }
done
                     

#################################
# Author:         NeuWings
# Create_Time:    2021/03/09
#################################
#!/bin/bash

[ -z "$1" -o -z "$2" ] && {
	echo Please Input Start/Stop Function And Service Name.
	exit
}

CHECK() {
[ -e "/usr/lib/systemd/system/$2" -o -e "/usr/lib/systemd/system/$2.service" ] &> /dev/null || {
  echo "$2 is not installed"
  exit
}
systemctl start $2 &> /dev/null && {
  echo "$2 Service $1 successful"
} || {
  echo "$2 Service $1 failed"
  echo "Unknown Error"
}
}

if [ "$1" = "start" ]
then
	CHECK $1 $2
elif [ "$1" = "stop" ]
then
	CHECK $1 $2
else
	echo "Please Input Right Function"
fi

采用文件内容批量建立用户

• 执行user_create.sh userlist passlist
• 建立userlist列表中的用户
• 设定userlist列表中的密码为passlist列表中的密码
• 当脚本后面跟的文件个数不足两个时,报错
• 当文件行数不一致时,报错
• 当用户存在时,报错

#################################
# Author:         NeuWings
# Create_Time:    2021/03/10
#################################
#!/bin/bash

[ $USER = "root" ] || {
	echo  "This Script Must Run As Root"
  exit
}

[ $# -eq 2 ] || {
	echo "Please Input Userlist and Passlist"
  exit
}

[ -e $1 ] || {
	echo "Userlist File is not exist"
	exit
}

[ -e $2 ] || {
  echo "Passlist File is not exist"
  exit
}

[ -f $1 ] || {
  echo "$1 is unavailable"
  exit
}

[ -f $2 ] || {
  echo "$2 is unavailable"
  exit
}

USERLINE=`awk 'BEGIN{n=0}{n++}END{print n}' $1`
PASSLINE=`awk 'BEGIN{n=0}{n++}END{print n}' $2`

[ $USERLINE != $PASSLINE ] && {
	echo "Different Lines"
	exit
}

for NUM in `seq 1 $USERLINE`
do
        USERNAME=`sed -n ${NUM}p $1`
        PASSWORD=`sed -n ${NUM}p $2`
				id $USERNAME &> /dev/null && {
          echo $USERNAME is exist!
        } || {
        useradd $USERNAME &> /dev/null || {
					echo "$USERNAME Create Failed,Unknown Error."
				} && {
        	echo $PASSWORD | passwd --stdin $USERNAME &> /dev/null
        	echo "$USERNAME Create success";
					}
        }
done

数据库备份脚本

• 指定db_dump.sh Test(数据库密码)
• 脚本执行后会备份数据库中的所有库到/mnt/mysqldump目录
• 备份文件名称为"库名称.sql",当此文件存在时进行分支选择
• 输入S跳过备份,输入B备份"库名称.sql"为"库名称_backup.sql",输入O覆盖原文件

#################################
# Author:         NeuWings
# Create_Time:    2021/03/10
#################################
#!/bin/bash

DB_ACTION() {
	read -p "Please input your action: " ACTION
	case $ACTION in
		B|b|Backup|backup)
		mv /mnt/mysqldump/$DBNAME.sql /mnt/mysqldump/${DBNAME}_backup.sql
  		mysqldump -uroot -p$1 $DBNAME > /mnt/mysqldump/$DBNAME.sql
		;;
		O|o|Overwrite|overwrite)
		mysqldump -uroot -p$1 $DBNAME > /mnt/mysqldump/$DBNAME.sql
		;;
		S|s|Skip|skip)
		;;
		*)
		echo "Please Input Right Action"
		DB_ACTION $1
		;;
	esac
}

[ -z "$1" ] && {
  echo "Please Input DB's Password"
  exit 1
}

rpm -q mariadb-server &> /dev/null

if [ "$? -ne 0" ]
then
	echo "Error: DBis not installed"
	exit 1
else
	if [ ! -e "/var/lib/mysql/mysql.sock" ]
	then
		echo "Error: DB is not running"
		exit 1
	else
		CHECK_DB=`mysql -uroot -p$1 -NEe "SHOW DATABASES;" 2> /dev/null`
		[ "$?" -ne "0" ] && {
			echo "Error: Wrong Password!"
			exit 1
		} || {
			DB_List=`echo "$CHECK_DB" | awk '!/^*|schema$/{print}'`
		}
	fi
fi

if [ ! -e "/mnt/mysqldump" ]
then
	mkdir /mnt/mysqldump
elif [ ! -d "/mnt/mysqldump" ]
then
	ehco "Error: /mnt/mysqldump is exist but not a directory"
	exit 1
fi

for DBNAME in $DB_List
do
	if [ ! -e "/mnt/mysqldump/$DBNAME.sql" ]
	then
		mysqldump -uroot -p$1 $DBNAME > /mnt/mysqldump/$DBNAME.sql
	else
		echo "/mnt/mysqldump/$DBNAME.sql is exist"
		echo "please choose what to do: "
		echo "[S]kip [B]ackup [O]verwrite"
		DB_ACTION $1
	if
done

系统性能检测脚本

• 执行check_upload.sh
• 显示效果如下
• CPU: 实际用量%
• MEM: 实际用量%

ps ax -o %cpu | awk 'BEGIN{CPU=0}!/%CPU|0.0/{CPU+=$1}END{print "CPU:    "CPU"%"}'
ps ax -o %mem | awk 'BEGIN{MEM=0}!/%MEM|0.0/{MEM+=$1}END{print "内存:    "MEM"%"}'