一、几个脚本的编写：
1、编写脚本/root/bin/systeminfo.sh,显示当前主机系统信息，包括主机名，IPv4地址，操作系统版本，内核版本，CPU型号，内存大小，硬盘大小。
#!/bin/bash echo "HOSTNAME: $HOSTNAME" echo "IPV4 ADDRESS: `ip a |grep "\<inet\>[ ].*brd"|tr -s " "|cut -d" " -f 3|tr '\n' ' '`" echo "OS RELEASE: `cat /etc/centos-release`" echo "CPU INFORMATION: `lscpu | grep "Model name"|tr -s " "|cut -d: -f2 |sed -r 's@[ ](.*)@\1@'`" echo "KERNEL RELEASE:`uname -r`" echo "MEMORY INFORMATION: ` cat /proc/meminfo|head -n 1|cut -d: -f 2|tr -d " "`" echo "HARD DISK INFOMATION:"` fdisk -l |grep "Disk.*sd"|cut -d: -f2|cut -d ' ' -f2,3|tr -d ','`
测试运行：
HOSTNAME: centos7.localdomain IPV4 ADDRESS: 10.1.255.177/16 192.168.122.1/24 OS RELEASE: CentOS Linux release 7.2.1511 (Core) CPU INFORMATION: AMD E2-1800 APU with Radeon(tm) HD Graphics KERNEL RELEASE:3.10.0-327.el7.x86_64 MEMORY INFORMATION: 1001336kB HARD DISK INFOMATION:107.4 GB
2、编写脚本/root/bin/backup.sh，可实现每日将/etc/目录备份到/root/etcYYYY-mm-dd中
#!/bin/bash #author jack_cui #version 1.0 #description: backup directory read -p "please input backup directory: " backdir read -p "please input destination directory: " desdir cp -r $backdir $desdir/backup`date +%F` echo "backup successful!"
测试运行：
[root@centos7 bin]# backup.sh please input backup directory: /root/bin/ please input destination directory: /testdir/ backup successful! [root@centos7 bin]# ls /testdir backup2016-08-12 fs.txt info.txt info.txt.bak info.txt.bak.backup vimtu
3、编写脚本/root/bin/disk.sh,显示当前硬盘分区中空间利用率最大的值
[root@centos7 bin]# cat disk.sh #!/bin/bash #author:jack_cui #description=show the system disk use disk_use=`df |grep sd|tr -s " "|cut -d " " -f5|sed -n 's/%//p'|sort -rn|head -n 1` echo $disk_use unset disk_use
测试运行：
[root@centos7 bin]# bash disk.sh 63
4、编写脚本/root/bin/links.sh,显示正连接本主机的每个远程主机的IPv4地址和连接数，并按连接数从大到小排序
[root@centos7 bin]# cat link.sh #!/bin/bash #author:jackcui #description: disk use infomation netstat -nt |tr -s ' '|cut -d ' ' -f5 |cut -d: -f1 |grep [0-9]|sort |uniq -c|sort -nr [root@centos7 bin]# link.sh 5 10.1.1.88
5、写一个脚本/root/bin/sumid.sh，计算/etc/passwd文件中的第10个用户和第20用户的ID之和
#!/bin/bash #author:jackcui #description:sum two user's id numbera=`sed -n '10p' /etc/passwd |cut -d: -f3` numberb=`sed -n '20p' /etc/passwd |cut -d: -f3` let suma_b=numbera+numberb echo "user1 uig is $numbera" echo "user2 uid is $numberb" echo "two users id sum is $suma_b" unset numberb suma_b numbera [root@centos7 bin]# sumid.sh user1 uig is 11 user2 uid is 59 two users id sum is 70
6、写一个脚本/root/bin/sumspace.sh，传递两个文件路径作为参数给脚本，计算这两个文件中所有空白行之和
两个测试文本：test.txt test2.txt 中间有6个空白行或全是空白字符的行
[root@centos7 ~]# cat test.txt aaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbbbbbbbb ccccccccccccccccccc [root@centos7 ~]# cat test2.txtt cat: test2.txtt: No such file or directory [root@centos7 ~]# cat test2.txt cccccccccccccccccccccccc bbbbbbbbbbbbbbbbbbbbbbbbbb cccccccccccccccc
脚本：
[root@centos7 bin]# cat sumspace.sh #!/bin/bash #author:jackcui #description:calculate two files blank line read -p "Input first path of files: " first_path read -p "Input second path of files:" second_path a=`cat $first_path |grep -e "^$" -e "[[:space:]]\+$" |wc -l` b=`cat $second_path |grep -e "^$" -e "[[:space:]]\+$" |wc -l` let sum=a+b echo "The total blank lines is: $sum" unset a b sum
脚本运行：
[root@centos7 bin]# sumspace.sh Input first path of files: /root/test.txt Input second path of files:/root/test2.txt The total blank lines is: 6
7、写一个脚本/root/bin/sumfile.sh,统计/etc, /var, /usr目录中共有多少个一级子目录和文件
[root@centos7 bin]# cat sumfile.sh #!/bin/bash #author:jackcui #description:sum directorys's files and directorys a=`ls -A /etc/|wc -l` b=`ls -A /var/|wc -l` c=`ls -A /usr/|wc -l` let sumfile=a+b+c echo "three directory have $sumfile files and directorys" unset a b c sumfile
脚本运行：
[root@centos7 bin]# sumfile.sh three directory have 296 files and directorys
8、写一个脚本/root/bin/argsnum.sh，接受一个文件路径作为参数；如果参数个数小于1，则提示用户“至少应该给一个参数”，并立即退出；如果参数个数不小于1，则显示第一个参数所指向的文件中的空白行数
[root@centos7 bin]# cat argsnum.sh #!/bin/bash #author:jackcui #description:dispaly file blank lines count [ "$#" -lt 1 ]&& echo "You should give one parameter!" && exit line=`cat $1|grep -c "^[[:space:]]*$" 2> /dev/null` echo $line unset line exit [root@centos7 bin]# argsnum.sh /root/test.txt 3 [root@centos7 bin]# argsnum.sh //没有参数时直接退出，并打印提示信息 You should give one parameter!
9、写一个脚本/root/bin/hostping.sh，接受一个主机的IPv4地址做为参数，测试是否可连通。如果能ping通，则提示用户“该IP地址可访问”；如果不可ping通，则提示用户“该IP地址不可访问”
[root@centos7 bin]# cat hostping.sh #!/bin/bash #author:jackcui #description:Judge a ip address whether access ping -W 1 -c3 $1 > /dev/null 2>&1 //指定ping超时时间1s，ping3次 suss=`echo $?` [ $suss -eq 0 ] && echo "IP address can access!"|| echo "IP address can not access!" [root@centos7 bin]# bash hostping.sh 10.1.0.2 //ping 不存在的地址报错 IP address can not access! [root@centos7 bin]# bash hostping.sh 10.1.0.1 //ping 存在的地址提示地址可以访问 IP address can access!
10、判断硬盘的每个分区空间和inode的利用率是否大于80，如果是，发邮件通知root磁盘满
[root@centos7 bin]# cat diskAlarm.sh
#!/bin/bash #author:jackcui #description:show the disk use diskuse=`df |grep 'sd'|tr -s " " |cut -d " " -f 5|sed -n 's/%//p'|sort -rn|head -n1` inodeuse=` df -i|grep 'sd'|tr -s " "|cut -d" " -f 5|sed -n 's/%//p'|sort -rn|head -n1` #[ $diskuse -ge 80 ]||[ $inodeuse -ge 80 ]&&echo "Dear root, disk has used too much!!!"|mail -s "Disk alarm!" root [ $diskuse -ge 80 -o $inodeuse -ge 80 ]&&echo "Dear root, disk has used too much!!!"|mail -s "Disk alarm!" root
测试运行：
[root@centos7 bin]# diskAlarm.sh [root@centos7 bin]# mail Heirloom Mail version 12.5 7/5/10. Type ? for help. "/var/spool/mail/root": 1 message 1 new >N 1 root Sat Aug 13 12:49 18/626 "Disk alarm!" & q Held 1 message in /var/spool/mail/root
11、指定文件做为参数，判断文件是否为.sh后缀，如果是，添加x权限
[root@centos7 bin]# cat ifsh.sh #!/bin/bash #author:jack_cui #description:show the file whether ended “.sh” [[ "$1" =~ .*\.sh$ ]]&&chmod a+x $1||echo "file is not ended '.sh'" [root@centos7 bin]# touch bb.sh [root@centos7 bin]# ifsh.sh bb.sh [root@centos7 bin]# ll bb.sh -rwxr-xr-x. 1 root root 0 Aug 13 13:59 bb.sh [root@centos7 bin]#
12、判断输入的IP是否为合法IP
[root@centos7 bin]# cat ipcorrect.sh
#!/bin/bash
#author:jack_cui
#description:display input ip whether correct!"
corr=`echo $1 |grep -E "(\<([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\>.){3}\<([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\>"|wc -l`
[ $corr -ne 0 ]&&echo "The IP address is correct!"||echo "The IP is not correct!"
执行结果：
[root@centos7 bin]# ipcorrect.sh 2.2.2.2 The IP address is correct! [root@centos7 bin]# ipcorrect.sh 233.2333.333.2 The IP is not correct!
13、计算1+2+3+…+100
[root@centos7 bin]# cat sum1_100 #!/bin/bash #author:jackcui #description:Add 1 to 100 sum=`seq -s "+" 1 100 |bc` echo "Add 1 to 100 sum is : $sum" [root@centos7 bin]# sum1_100 Add 1 to 100 sum is : 5050
14、输入起始值A和最后值B，计算从A+（A+1）…+(B-1)+B的总和
[root@centos7 bin]# cat A2Bsum.sh #!/bin/bash #author:jackcui #description:calculator A to B (A and B is two number),INCREMENT can be given,for eg:A=2,B=6,INCREMENT is 2 ,the sum=2+4+6=12; read -p "Input first number: " A read -p "Input second number: " B read -p "Iput INCREMENT number: " I echo "The sum is : `seq -s '+' $A $I $B|bc`" unset A B I [root@centos7 bin]# A2Bsum.sh Input first number: 2 Input second number: 4 Iput INCREMENT number: 1 //递增值为1 The sum is : 9 [root@centos7 bin]# A2Bsum.sh Input first number2 //计算2至6递增值为2的数字的和 Input second number6 Iput INCREMENT number2 //递增值为2 The sum is : 12
注释：seq –s 指定分割符为” + ” ，seq可以产生递增性的数字，之后传值给bc命令进行计算
二、位置变量$0 $1,$2,$# $@ $*的区别：
$0 :表示执行命令时，命令本身；
$1:表示命令的第一个参数
$#:表示命令的参数的个数
$@,$*：这两个只有在命令的参数用引号括起来时，前者表示在引号中以空格为分隔符，将引号中的多段分别当成一个参数传递值脚本，后者表示将引号中字符串当成一个参数传递至脚本
原创文章，作者：jack_cui，如若转载，请注明出处：http://www.178linux.com/34801
