写一个脚本：
1.提示用户选择所要设置的网卡；
2.提示用户使用dhcp或者static'作为选定网卡的BOTOPROTO
a.如果用户选择dhcp，则将其配置文件中的BOOTPROTO的值设为dhcp，而后重启网卡；
b.如果用户选择static，则将其配置文件中的BOOTPROTO的值设static,并提示用户输入IP地址，子网掩码和网关；其中网关可以为空，但IP地址或子网掩码不能为空；设置完成后重启次网卡；
3.无论上述动态或静态设定，设定完成后将网卡IP地址设定后信息再次显示给用户
#!/bin/bash
NPATH="/etc/sysconfig/network-scripts/"
echo "Please select the network card:"
read -p "`ls $NPATH|grep ifcfg|cut -d- -f2`:" A
read -p "Please select the BOOTPROTO between dhcp and static:" B
if [ $B = "dhcp" ];then
sed -i 's/\(BOOTPROTO=\).*/\1dhcp/g' $NPATH"ifcfg-"$A
service network restart
elif [ $B = "static" ];then
sed -i 's/\(BOOTPROTO=\).*/\1static/g' $NPATH"ifcfg-"$A
read -p "Please input IP:" IP
[ ! -n "$IP" ]&&echo "input error!!!"&&exit 5
sed -i 's/\(IPADDR=\).*/\1'''$IP'''/g' $NPATH"ifcfg-"$A
read -p "Please input netmask:" MK
[ ! -n "$MK" ]&&echo "input error!!!"&&exit 5
sed -i 's/\(NETMASK=\).*/\1'''$MK'''/g' $NPATH"ifcfg-"$A
read -p "Please input gateway:" GW
sed -i 's/\(GATEWAY=\).*/\1'''$GW'''/g' $NPATH"ifcfg-"$A
service network restart
fi
cat $NPATH"ifcfg-"$A
