查看系统中允许登陆的用户
[root@136 mnt]# vim show_loginsuer.sh
[root@136 mnt]# cat show_loginsuer.sh
#!/bin/bash
SHELL=$(echo `grep -v nologin /etc/shells` | sed 's/ /|/g')
grep -E "$SHELL" /etc/passwd | cut -d : -f 1
[root@136 mnt]# chmod +x show_loginsuer.sh
[root@136 mnt]# /mnt/show_loginsuer.sh
root
student
[root@136 mnt]# useradd -s /bin/tcsh hello
[root@136 mnt]# /mnt/show_loginsuer.sh
root
student
hello
[root@136 mnt]#
显示ip
[root@136 mnt]# vim ip_show.sh
[root@136 mnt]# ifconfig eth0 | awk -F " " '/inet\>/{print $2}'172.25.254.136
[root@136 mnt]# awk -F "=" '/^IPAD/{print $2}' /etc/sysconfig/network-scripts/ifcfg-Ethernet_connection_1
172.25.254.136
[root@136 mnt]# cat ip_show.sh
#!/bin/bash
ifconfig eth0 | awk -F " " '/inet\>/{print $2}'
[root@136 mnt]# sh ip_show.sh
172.25.254.136
[root@136 mnt]# 统计文件行数
[root@136 mnt]# awk 'BEGIN{N=0}{N++}END{print N}' passwd
28
[root@136 mnt]# vim tongjihang.sh
[root@136 mnt]# cat tongjihang.sh
#!/bin/bash
awk 'BEGIN{N=0}{N++}END{print N}' passwd
[root@136 mnt]# sh tongjihang.sh
28
安装 httpd，并修改端口为所跟port
[root@136 ~]# vim install_apache.sh
[root@136 ~]# cat install_apache.sh
#!/bin/bash
[ "$#" -eq "1" ]||{
echo "Please input port after script!!"
exit 1
}
yum install httpd -y &> /dev/null
sed "/^Listen/cListen $1" -i /etc/httpd/conf/httpd.conf
systemctl restart httpd
echo -e "\033[32mThe Listen is changed!!\033[0m"
netstat -antulpe | grep http
[root@136 ~]# sh install_apache.sh 66
The Listen is changed!!
tcp6 0 0 :::66 :::* LISTEN 0 70735 2584/httpd 实现在执行脚本后跟两个参数，userfile、passfile，创建userfile中的用户，并添加passfile中的密码给用户
[root@136 ~]# vim userfile
[root@136 ~]# cat userfile
user1
user2
user3
[root@136 ~]# vim passfile
[root@136 ~]# cat userfile
user1
user2
user3
[root@136 ~]# vim create_user.sh
[root@136 ~]# sh create_user.sh userfile passfile
user1
123
user2
123
user3
123
[root@136 ~]# cat create_user.sh
#!/bin/bash
MAX_LINE=`wc -l $1 | cut -d " " -f 1`
for LINE_NUM in `seq 1 $MAX_LINE`
do
sed -n "${LINE_NUM}p" $1
sed -n "${LINE_NUM}p" $2
done
[root@136 ~]# vim create_user.sh
[root@136 ~]# cat create_user.sh
#!/bin/bash
MAX_LINE=`wc -l $1 | cut -d " " -f 1`
for LINE_NUM in `seq 1 $MAX_LINE`
do
USERNAME=`sed -n "${LINE_NUM}p" $1`
PASSWORD=`sed -n "${LINE_NUM}p" $2`
useradd $USERNAME
echo $PASSWORD | passwd --stdin $USERNAME
done
[root@136 ~]# sh create_user.sh userfile passfile
Changing password for user user1.
passwd: all authentication tokens updated successfully.
Changing password for user user2.
passwd: all authentication tokens updated successfully.
Changing password for user user3.
passwd: all authentication tokens updated successfully.若没有跟两个文件参数，将报错
[root@136 ~]# vim create_user.sh
[root@136 ~]# cat create_user.sh
#!/bin/bash
[ "$#" -ne "2" ]&&{
echo -e "\033[31mERROR:please input userfile and passwordfile\033[0m"
exit 1
}
MAX_LINE=`awk 'BEGIN{N=0}{N++}END{print N}' $1`
for LINEMAX in `seq 1 $MAX_LINE`
do
USERNAME=$(sed -n "${LINEMAX}P" $1)
PASSWORD=$(sed -n "${LINEMAX}P" $2)
useradd $USERNAME
echo $PASSWORD | passwd --stdin $USERNAME
done
[root@136 ~]# sh create_user.sh
ERROR:please input userfile and passwordfile
[root@136 ~]# sh create_user.sh userfile
ERROR:please input userfile and passwordfile
[root@136 ~]# sh create_user.sh userfile passfile
useradd: user 'user1' already exists
Changing password for user user1.
passwd: all authentication tokens updated successfully.
useradd: user 'user2' already exists
Changing password for user user2.
passwd: all authentication tokens updated successfully.
useradd: user 'user3' already exists
Changing password for user user3.
passwd: all authentication tokens updated successfully.
[root@136 ~]#
修改为交互
[root@136 ~]#
[root@136 ~]# vim create_user.sh
[root@136 ~]# cat create_user.sh
#!/bin/bash
read -p "Please input userfile:" USER
[ -e "$USER" ]||{
echo -e "\033[31mERROR: $USER is not exist!!\033[0m"
exit 1
}
read -p "Please input passwordfile:" PASSWORDFILE
[ -e "$PASSWORDFILE" ]||{
echo "\033[31mERROR: $PASSWORDFILE is not exist!!\033[0m"
exit 1
}
MAX_LINE=`awk 'BEGIN{N=0}{N++}END{print N}' $USER`
for LINEMAX in `seq 1 $MAX_LINE`
do
USERNAME=$(sed -n "${LINEMAX}P" $USER)
PASSWORD=$(sed -n "${LINEMAX}P" $PASSWORDFILE)
useradd $USERNAME
echo $PASSWORD | passwd --stdin $USERNAME
done
[root@136 ~]# sh create_user.sh
Please input userfile:userfile
Please input passwordfile:passfile
useradd: user 'user1' already exists
Changing password for user user1.
passwd: all authentication tokens updated successfully.
useradd: user 'user2' already exists
Changing password for user user2.
passwd: all authentication tokens updated successfully.
useradd: user 'user3' already exists
Changing password for user user3.
passwd: all authentication tokens updated successfully.
脚本中的函数是把一个复杂的语句块定义成一个字符串的方法
[root@136 ~]# vim ip.sh
[root@136 ~]# cat ip.sh
#!/bin/bash
PING()
{
read -p "Please input a idaddress: " IP
ping -c1 -w1 $IP &> /dev/null && echo $IP is up || echo $IP is down
PING
}
PING
[root@136 ~]# sh ip.sh
Please input a idaddress: 172.25.254.63
172.25.254.63 is up
Please input a idaddress: 172.25.254.11
172.25.254.11 is down
Please input a idaddress: ^C
[root@136 ~]#
增加输入exit退出
[root@136 ~]# vim ip.sh
[root@136 ~]# cat ip.sh
#!/bin/bash
PING()
{
read -p "Please input a idaddress: " IP
[ "$IP" = exit ]&&{
echo bye
exit 0
}
ping -c1 -w1 $IP &> /dev/null && echo $IP is up || echo $IP is down
PING
}
PING
[root@136 ~]# sh ip.sh
Please input a idaddress: 172.25.254.63
172.25.254.63 is up
Please input a idaddress: exit
bye
[root@136 ~]#
[root@136 ~]# vim file_check.sh
[root@136 ~]# cat file_check.sh
#!/bin/bash
FILE_CHECK()
{
[ "$1" "$2" ]&&{
echo $2 is $3
exit 0
}
}
[ -e "$1" ]||{
echo $1 is not exist!!
echo 0
}
FILE_CHECK -L $1 link
FILE_CHECK -f $1 file
[root@136 ~]# sh file_check.sh /etc/passwd
/etc/passwd is file
[root@136 ~]# sh file_check.sh /etc/system-release
/etc/system-release is link
[root@136 ~]# vim useraction_check.sh
[root@136 ~]# cat useraction_check.sh
#!/bin/bash
USERADD(){
[ "$1" = add ]&&{
read -p "plesae input addusername: " USERA
read -p "plesae input addpassword: " -s PASSWORD
echo ""
useradd $USERA
echo $PASSWORD | passwd --stdin $USERA
}
}
USERDEL(){
[ "$1" = del ]&&{
read -p "plesae input username: " USERNAME
userdel -r $USERNAME
}
}
USERACTION(){
read -p "please input action: " ACTION
[ "$ACTION" = exit ]&&{
echo "bye"
exit 0
}
USERADD $ACTION
USERDEL $ACTION
USERACTION
}
USERACTION
[root@136 ~]# sh useraction_check.sh
please input action: add
plesae input addusername: haha
plesae input addpassword:
Changing password for user haha.
passwd: all authentication tokens updated successfully.
please input action: del
plesae input username: haha
please input action: 123
please input action: exit
bye