Problema con 2 decos en misma LAN... Problema con la MAC.

[COLOR=#242626][FONT=Consolas]$ ifconfig -a | grep HWaddr
[/FONT][/COLOR][COLOR=#242626][FONT=Consolas]eth0  Link encap:Ethernet HWaddr [/FONT][/COLOR][COLOR=blue][FONT=Consolas]00:80:48:BA:d1:20[/FONT][/COLOR]

[COLOR=#242626][FONT=Consolas]# ifconfig eth0 down[/FONT][/COLOR]
# ifconfig eth0 hw ether [COLOR=blue]00:80:48:BA:d1:30
[/COLOR]# ifconfig eth0 up 
[COLOR=#242626][FONT=Consolas]# ifconfig eth0 |grep HWaddr[/FONT][/COLOR]

#!/bin/sh#
# manage network interfaces and configure some networking options


PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin


if ! [ -x /sbin/ifup ]; then
    exit 0
fi


spoofprotect_rp_filter () {
    # This is the best method: turn on Source Address Verification and get
    # spoof protection on all current and future interfaces.
    
    if [ -e /proc/sys/net/ipv4/conf/all/rp_filter ]; then
        for f in /proc/sys/net/ipv4/conf/*; do
        [ -e $f/rp_filter ] && echo 1 > $f/rp_filter
        done
        return 0
    else
        return 1
    fi
}


spoofprotect () {
    echo -n "Setting up IP spoofing protection: "
    if spoofprotect_rp_filter; then
        echo "rp_filter."
    else
        echo "FAILED."
    fi
}


ip_forward () {
    if [ -e /proc/sys/net/ipv4/ip_forward ]; then
        echo -n "Enabling packet forwarding... "
        echo 1 > /proc/sys/net/ipv4/ip_forward
        echo "done."
    fi
}


syncookies () {
    if [ -e /proc/sys/net/ipv4/tcp_syncookies ]; then
        echo -n "Enabling TCP/IP SYN cookies... "
        echo 1 > /proc/sys/net/ipv4/tcp_syncookies
        echo "done."
    fi
}


doopt () {
    optname=$1
    default=$2
    opt=`grep "^$optname=" /etc/network/options`
    if [ -z "$opt" ]; then
        opt="$optname=$default"
    fi
    optval=${opt#$optname=}
    if [ "$optval" = "yes" ]; then
        eval $optname
    fi
}


[COLOR=#ff0000]cambiaMAC () {[/COLOR]
[COLOR=#ff0000] ifconfig eth0 down[/COLOR]
[COLOR=#ff0000] ifconfig eth0 hw ether 00:80:48:BA:d1:30[/COLOR]
[COLOR=#ff0000]ifconfig eth0 up[/COLOR]
[COLOR=#ff0000]}[/COLOR]


case "$1" in
    start)
        if sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\1 \2/p' /proc/mounts | 
          grep -q "^/ nfs$"; then
            echo "NOT configuring network interfaces: / is an NFS mount"
        elif sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\1 \2/p' /proc/mounts |  
          grep -q "^/ smbfs$"; then
            echo "NOT configuring network interfaces: / is an SMB mount"
    elif sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\2/p' /proc/mounts | 
          grep -qE '^(nfs|smbfs|ncp|coda)$'; then
            echo "NOT configuring network interfaces: network shares still mounted."
        else
            echo -n "Configuring network interfaces... "
            ifup -a
        echo "done."
         # /etc/sysctl.conf is preferred
        if [ ! -f /etc/sysctl.conf ]; then
          doopt spoofprotect yes
          doopt syncookies no
          doopt ip_forward no
        fi
      fi
[COLOR=#ff0000]      cambiaMAC[/COLOR]
      ;;
    stop)
        if sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\1 \2/p' /proc/mounts | 
          grep -q "^/ nfs$"; then
            echo "NOT deconfiguring network interfaces: / is an NFS mount"
        elif sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\1 \2/p' /proc/mounts |  
          grep -q "^/ smbfs$"; then
            echo "NOT deconfiguring network interfaces: / is an SMB mount"
    elif sed -n 's/^[^ ]* \([^ ]*\) \([^ ]*\) .*$/\2/p' /proc/mounts | 
          grep -qE '^(nfs|smbfs|ncp|coda)$'; then
            echo "NOT deconfiguring network interfaces: network shares still mounted."
        else
            echo -n "Deconfiguring network interfaces... "
            ifdown -a
        echo "done."
        fi
    ;;
    force-reload|restart)
        echo -n "Reconfiguring network interfaces... "
        ifdown -a
        ifup -a
    echo "done."
    ;;
    *)
    echo "Usage: /etc/init.d/networking {start|stop|restart|force-reload}"
    exit 1
    ;;
esac


exit 0