getip.sh

shell 简单例程,含数学计算IP获取awk例程字数统计示例

#!/bin/bash
# getip.sh -- get an usable ipaddress automatically
# author: falcon <[e-mail]>
# update: Tue Oct 30 23:46:17 CST 2007

net="192.168.1"
default_gateway="192.168.1.239"
over_time=2

# check the current ipaddress
ping -c 1 $default_gateway -W $over_time
[ $? -eq 0 ] && echo "the current ipaddress is okey\!" && exit -1;

while :; do
	# clear the current configuration
        ifconfig eth0 down
        # configure the ipaddress of the eth0
        ifconfig eth0 \
                $net.$(($RANDOM /130 +2)) \
                up 
        # configure the default gateway
        route add default gw $default_gateway
        # check the new configuration
        ping -c 1 $default_gw -W $over_time
        # if work, finish
        [ $? -eq 0 ] && break
done