1、用for循环批量修改文件扩展名(P240) 2、使用专业改名命令rename来实现 3、通过脚本实现sshd、rsyslog、crond、network、sysstat服务在开机时自动启动(P244) 4、打印99乘法表(P246) 5、用for循环打印1到100的和(P247) 6、批量创建10个系统账号,并设置密码(P255) 7、Linux系统产生随机数的6中方法(P257) 8、select循环(P259) 9、break、continue、return、exit脚本演练
10、开发shell脚本实现为服务配置多个IP(P271)
11、利用RANDOM生成随机一段文字并利用md5sum加密保存到一个文件中,根据指定字符串(1ea2edc6fe31)找出破解其加密前的数字(P275)
12、通过C语言型的for循环语句打印数组元素(P283)
13、利用for循环语句打印字母数大于等于4的单词(P286)
14、批量检查多个网址是否正常(P287)
15、检查MySQL主从复制是否正常(P291)
1、用for循环批量修改文件扩展名(P240)
2、使用专业改名命令rename来实现
3、通过脚本实现sshd、rsyslog、crond、network、sysstat服务在开机时自动启动(P244)
使用循环
#for i in `chkconfig --list | grep 3:on | awk '{print $1}'`; do chkconfig --level 3 $i off; done
通过bash命令
chkconfig --list | grep 3:off | grep -vE "iscsi|iscsid|multipathor|netconsole|netfs|rdisc|restorecond|saslauthd" | awk '{print " chkconfig " $1 " on "}' | bash
4、打印99乘法表(P246)
1 #!/bin/bash 2 # 3 for num1 in `seq 9`; do 4 for num2 in `seq 9`; do 5 if [ $num1 -ge $num2 ]; then 6 if (((num1*num2)>9)); then //如果两个乘数相乘大于9,这是控制输出格式 7 echo -en "${num1}x${num2}=$((num1*num2)) " //结尾多一个空格 8 else 9 echo -en "${num1}x${num2}=$((num1*num2)) " //结尾多两个空格 10 fi 11 fi 12 done 13 14 echo " " 15 done [root@C ~]# bash 99.sh 1x1=1 2x1=2 2x2=4 3x1=3 3x2=6 3x3=9 4x1=4 4x2=8 4x3=12 4x4=16 5x1=5 5x2=10 5x3=15 5x4=20 5x5=25 6x1=6 6x2=12 6x3=18 6x4=24 6x5=30 6x6=36 7x1=7 7x2=14 7x3=21 7x4=28 7x5=35 7x6=42 7x7=49 8x1=8 8x2=16 8x3=24 8x4=32 8x5=40 8x6=48 8x7=56 8x8=64 9x1=9 9x2=18 9x3=27 9x4=36 9x5=45 9x6=54 9x7=63 9x8=72 9x9=81
5、用for循环打印1到100的和(P247)
1 #!/bin/bash 2 # 3 i=0 4 while ((i<=100)); do 5 ((sum=sum+i)) 6 ((i++)) 7 done 8 9 echo $sum
1 #!/bin/bash 2 # 3 for ((i=1;i<=100;i++)); do 4 ((sum=sum+i)) 5 done 6 7 echo $sum
# echo $(( (100+1) * 100/2))
6、批量创建10个系统账号,并设置密码(P255)
1 #!/bin/bash 2 # 3 . /etc/init.d/functions 4 user="cos" 5 passfile="/tmp/user.log" 6 7 echo ------this is my script for adding users------ 8 for num in `seq -w 10`; do 9 useradd $user$num 10 pass="`echo "cos$RANDOM" | md5sum | cut -c 5-12`" 11 12 echo -e "$user${num}:$pass" >>$passfile 13 14 if [ $? -eq 0 ]; then 15 action "Add $user$num is ok." /bin/true 16 else 17 action "Add $user$num is fail." /bin/true 18 fi 19 done 20 21 echo "----------Add Users----------" 22 chpasswd < $passfile &>/dev/null //读取密码文件进行密码设置 23 cat $passfile
1 #!/bin/bash 2 # 3 . /etc/init.d/functions 4 user="cos" 5 passfile="/tmp/user.log" 6 7 echo ------this is my script for adding users------ 8 for num in `seq -w 10`; do 9 useradd $user$num 10 pass="`echo "cos$RANDOM" | md5sum | cut -c 5-12`" 11 12 echo "$pass" | passwd --stdin $user$num &>/dev/null && 13 echo -e "user:$user$num passwd:$pass" >>$passfile 14 15 if [ $? -eq 0 ]; then 16 action "Add $user$num is ok." /bin/true 17 else 18 action "Add $user$num is fail." /bin/true 19 fi 20 done 21 22 echo "----------Add Users----------" 23 cat $passfile
#!/bin/bash # user="cos" passfile="/tmp/user.log" for num in `seq -w 10`; do id $user$num &>/dev/null if [ $? -eq 0 ]; then userdel -r $user$num echo "$user$num was delete." else echo "$user$num is not exist." fi done cat /dev/null >$passfile
7、Linux系统产生随机数的6中方法(P257)
1、通过系统环境变量($RANDOM)实现 # echo "hello world$RANDOM" | md5sum | cut -c 5-13 66f32895e
2、通过openssl产生随机数 数字和大小写字符、特殊字符相结合 # openssl rand -base64 80 eTlRKlp2r6v/cMt4C3lkNpSU1i/NV8oCnzvMA35zyXLLzQObS3jpjeh5w3doNINk MGl0gWXji4vupUDyIOUIGV1te25vn+EcJxEjKTt8wqg=
4、通过/dev/urandom配合chksum生成随机数 # head /dev/urandom | cksum 1284149441 4169
5、通过UUID产生随机数 # cat /proc/sys/kernel/random/uuid 4b3d6a51-990b-4993-b130-cc9dae5df37f
3、通过时间(date)产生随机数 # date +%s%N 1533976483650549026
6、使用expect附带的mkpasswd生成随机数 # yum install expect -y //安装expect # mkpasswd -l 9 -d 2 -c 3 -C 3 -s 1 | md5sum | cut -c 3-12 221d1f369b 相关参数说明: -l:指定密码长度 -d:指定密码中数字的数量 -c:指定密码中小写字母的数量 -C:指定密码中大写字母的数量 -s:指定密码中特殊字符的数量
8、select循环(P259)
1 #!/bin/bash 2 # 3 select name in xiaohong xiaoming xiaoqiang; do 4 echo $name 5 done 6
# bash 3.sh 1) xiaohong 2) xiaoming 3) xiaoqiang #? 1 xiaohong #? 2 xiaoming #? 3 xiaoqiang
采用数组做变量列表
1 #!/bin/bash 2 # 3 array=(hong ming qiang) 4 5 select name in "${array[@]}"; do 6 echo $name 7 done
把命令结果作为变量列表
1 #!/bin/bash 2 # 3 4 select name in `ls /etc`; do 5 echo $name 6 done
调整select循环菜单默提示符即利用select变量打印数字序号
1 #!/bin/bash 2 # 3 4 PS3="Please select a num from menu:" //PS3是控制select循环的提示符 5 select name in hong qiang ming; do 6 echo -e "You choice is: $REPLY) $name" //REPLY是菜单项对应的数字,即用户输入的数字 7 done 8 9 # bash 1.sh 10 1) hong 11 2) qiang 12 3) ming 13 Please select a num from menu:1 14 You choice is: 15 1) hong 16 Please select a num from menu:2 17 You choice is: 18 2) qiang
9、break、continue、return、exit脚本演练(P269)
1 #!/bin/bash 2 # 3 4 if [ $# -ne 1 ]; then 5 echo "Usage:$0 {break|continue|exit|return}" 6 exit 1 7 fi 8 9 test() { 10 for ((i=0;i<=5;i++)); do 11 if [ $i -eq 3 ]; then 12 $*; //如果$i=3,这里就接受函数外的参数,即test $* 13 fi 14 echo $i 15 done 16 echo "I am in func." 17 } 18 19 test $* 20 func_ret=$? 21 if [ `echo $* | grep return | wc -l` -eq 1 ]; then 22 echo "return is exit status:$func_ret" 23 fi 24 25 echo "ok"
continue是终止当前循环执行下一次循环,break是跳出当前循环(if循环),return是不但终止当前循环还跳出当前函数,exit是直接推出脚本
10、开发shell脚本实现为服务配置多个IP(P271)
1 #!/bin/bash 2 # 3 4 [ -f /etc/init.d/functions ] && . /etc/init.d/functions 5 op() { 6 if [ $1 == "del" ]; then 7 list=`echo {157..147}` 8 else 9 list=`echo {147..157}` 10 fi 11 12 for ip in $list; do 13 if [ $ip -eq 150 ]; then 14 continue 15 fi 16 ip addr $1 192.168.184.$ip/24 dev eth0 label eth0:$ip &>/dev/null 17 if [ $? -eq 0 ]; then 18 action "$1 $ip" /bin/true 19 else 20 action "$1 $ip" /bin/false 21 fi 22 done 23 } 24 25 case "$1" in 26 add) 27 op add ;; 28 del) 29 op del ;; 30 readd) 31 op del 32 echo "Ip was deleted" 33 sleep 3 34 echo "Ip will add" 35 op add ;; 36 *) 37 echo "Usage:$0 {add|del|readd}" 38 esac 39
使用ifconfig配置别名IP
#ifconfig eth0:0 192.168.184.147/24 up 添加IP
#ifconfig eth0:0 192.168.184.147/24 down 删除IP
使用IP命令配置ip
#ip addr add 192.168.184.147/24 dev eth0 label eth0:147 添加IP
#ip addr del 192.168.184.147/24 dev eth0 label eth0:147 删除IP
11、利用RANDOM生成随机一段文字并利用md5sum加密保存到一个文件中,根据指定字符串(1ea2edc6fe31)找出破解其加密前的数字(P275)
1 #!/bin/bash 2 # 3 4 #for n in {0..32767}; do //生成随机数,并保存到文件里面 5 # echo "`echo $n | md5sum` $n" >>/tmp/1.log 6 #done 7 8 md5char="1ea2edc6fe31" 定义要查找的字符串 9 #cat /tmp/1.log | while read line; do 10 while read line; do 11 if [ `echo $line | grep "$md5char" | wc -l` -eq 1 ]; then 12 echo $line 13 break 14 fi 15 done </tmp/1.log
RANDOM随机数范围再0~32767
读取文件中的每一行参考:https://www.cnblogs.com/demonxian3/p/7886177.html
数组
12、通过C语言型的for循环语句打印数组元素(P283)
1 #!/bin/bash 2 # 3 array=(1 2 3 4 5 6) 4 for ((i=0;i<${#array[*]};i++)); do 5 echo ${array[i]} 6 done 7 8 #!/bin/bash 9 # 10 array=(1 2 3 4 5 6) 11 for i in ${array[*]}; do 12 echo $i 13 done
1 #!/bin/bash 2 # 3 array=( 4 192.168.184.145 5 192.168.184.146 6 192.168.184.147 7 ) 8 9 #for ((i=0;i<${#array[@]};i++)); do //C语言for循环语法 10 # echo "${array[i]}" 11 #done 12 13 for n in ${array[*]}; do //普通for循环语法 14 echo $n 15 done
静态数组:array=(1 2 3) 动态数组:array=($(ls))
打印所有数组:${array[*]} ${array[@]}
打印数组长度:${#array[*]} ${#array[@]}
1 #!/bin/bash 2 # 3 array=( 4 192.168.184.145 5 192.168.184.146 6 192.168.184.147 7 ) 8 9 #for ((i=0;i<${#array[@]};i++)); do 10 # echo "${array[i]}" 11 #done 12 13 for n in ${array[*]}; do 14 echo $n 15 done
13、利用for循环语句打印字母数大于等于4的单词(P286)
1 #!/bin/bash 2 # 3 4 array=(I am exercising bash scripts I like it very much) 5 6 #for ((i=0;i<${#array[*]};i++)); do 7 # if [ ${#array[$i]} -ge 4 ]; then 8 # echo "${array[$i]}" 9 # fi 10 #done 11 12 for word in ${array[*]}; do 13 if [ `expr length $word` -ge 4 ]; then 14 echo $word 15 fi 16 done
14、批量检查多个网址是否正常(P287)
1 #!/bin/bash 2 # 3 . /etc/init.d/functions 4 5 check_count=0 6 url_list=( 7 http://www.baidu.com 8 https://i.cnblogs.com 9 https://hao.360.cn 10 http://www.ninini 11 https://www.sina.com.cn 12 ) 13 14 wait() { 15 echo -n '3秒后,执行检查URL操作.'; 16 for ((i=0;i<3;i++)); do 17 echo -n ".";sleep 1 18 done 19 echo 20 } 21 22 check_url() { 23 wait 24 for ((i=0;i<${#url_list[*]};i++)); do 25 wget -T 3 --tries=2 --spider ${url_list[$i]} &>/dev/null 26 if [ $? -eq 0 ]; then 27 action "${url_list[$i]}" /bin/true 28 else 29 action "${url_list[$i]}" /bin/false 30 fi 31 done 32 ((check_count++)) 33 } 34 35 main() { 36 while true; do 37 check_url 38 echo "----------check count:${check_count}-----------" 39 sleep 3 40 done 41 } 42 43 main
15、检查MySQL主从复制是否正常(P291)
slave.log
Slave_IO_Running:No
Slave_SQL_Running:No
Seconds_Behind_Master:0
1 #!/bin/bash 2 # 3 4 status=($(awk -F ':' '/_Running|_Behind/{print $NF}' slave.log)) 5 6 for ((i=0;i<${#status[*]};i++)); do 7 count=0 8 if [ "${status[${i}]}" != "yes" -a "${status[${i}]}" != 0 ]; then 9 let count+=1 10 fi 11 done 12 13 if [ $count -ne 0 ]; then 14 echo "mysql replcation is failed" 15 else 16 echo "mysql replcation is success" 17 fi