UNIX shell获取IP和修改IP

#!/bin/ksh

#全局变量
#已配置信息的网卡个数
ETHNUM=0
#网卡名称信息，多个网卡用#符号分隔
ETHS=""
#网卡IP/掩码/默认网关信息，用:符号分隔，多个网卡用#符号分隔
ETHINFO=""
#网卡名称信息，用数组存储
ETHSArray[0]=""
#网卡IP/掩码/默认网关信息，用数组存储
ETHINFOArray[0]=""
#修改IP时原IP所在网卡在数组中的索引
ETHINDEX=0

function getIP
{
typeset ethList="";
typeset ethaddr="";
typeset ethmask="";
typeset gateway="";
typeset ethinfo="";
# 获取所有网卡信息
ethList=`ifconfig -a | grep 'eth' | awk '{print $1}'`
# 循环所有网卡
for eth in ${ethList}
do
# 获取网卡IP地址
ethaddr=`ifconfig ${eth} | grep 'inet addr:'| awk '{print $2}' | awk -F : '{print $2}'`
# 网卡配置了IP地址
if [ "-$ethaddr" != "-" ]
then
# 获取网卡掩码
ethmask=`ifconfig ${eth} | grep 'inet addr:'| awk '{print $4}' | awk -F : '{print $2}'`
# 获取网卡默认网关
# gateway=`route ${eth}| grep default.*UG.*$eth | awk '{print $2}'`
gateway=`route | grep default.*UG.*$eth | awk '{print $2}'`
# 将该网卡的信息拼成字符串
ethinfo="${ethaddr}:${ethmask}:${gateway}"

ETHSArray[$ETHNUM]="$eth"
ETHINFOArray[$ETHNUM]="$ethinfo"
ETHNUM=`expr $ETHNUM + 1`

# ETHS为空字符串
if [ "-$ETHS" == "-" ]
then
ETHS="${eth}"
else
ETHS="${ETHS}#${eth}"
fi

# ETHINFO为空字符串
if [ "-$ETHINFO" == "-" ]
then
ETHINFO="${ethinfo}"
else
ETHINFO="${ETHINFO}#${ethinfo}"
fi

fi

done

return 0
}

function modifyIP
{
# 保证输入4个参数
if [ $# -ne 4 ]; then
echo "The parameters is not 4!"
return 1
fi

typeset oldIP=$1
typeset newIP=$2
typeset newmask=$3
typeset newgw=$4

# 获取当前网卡信息
getIP

# 判断该原IP是否存在
get_eth_of_IP $oldIP
# 原IP不存在，返回1
if [ $ -ne 0 ]; then
echo "The old IP $oldIP is not exist."
return 1
fi

typeset eth="${ETHSArray[$ETHINDEX]}"
typeset ethinfo="${ETHINFOArray[$ETHINDEX]}"
typeset ethaddr=`echo $ethinfo | awk -F: '{print $1}'`
typeset ethmask=`echo $ethinfo | awk -F: '{print $2}'`
typeset ethgw=`echo $ethinfo | awk -F: '{print $3}'`

# 即时生效方式修改IP
echo "ifconfig $eth $newIP netmask $newmask"
ifconfig $eth $newIP netmask $newmask
if [ "$ " -ne 0 ]; then
echo "Modify old IP $oldIP to new IP $newIP failed."
return 1
fi

# 永久生效方式修改IP
sed "s/$oldIP/$newIP/" /etc/sysconfig/network/ifcfg-$eth > /tmp/ifcfgtemp
sed "s/$ethmask/$newmask/" /tmp/ifcfgtemp > /etc/sysconfig/network/ifcfg-$eth
rm /tmp/ifcfgtemp

#即时生效方式修改网关
route del default
echo "route del default"
route add default gw $newgw dev $eth
echo "route add default gw $newgw dev $eth"

# 永久生效方式修改网关
sed "s/$ethgw/$newgw/" /etc/sysconfig/network/routes > /tmp/routetemp
mv /tmp/routetemp /etc/sysconfig/network/routes

return 0
}