@echo off
setlocal enableDelayedExpansion

for /f "delims=" %%a in ('ipconfig /all') do (
    set line=%%a
    if not "!line:~0,1!"==" " if not "!line:adapter=!"=="!line!" (
        set name=!line:*adapter =!
        set name=!name::=!
    )

    for /f "tokens=1,2,*" %%b in ("%%a") do (
        if "%%b %%c"=="Physical Address." (
            set mac=%%d
            set mac=!mac:*: =!
            set mac=!mac:-=:!
            call :tolower mac

            if "00-f0-54-1a-7e-e0"=="!mac!" (
                                    echo DHCP is active
                                                    netsh interface set interface name="!name!" newname="eth0"
                                                                    )
        )
    )
)
call :done

:tolower
for %%L IN (a b c d e f g h i j k l m n o p q r s t u v w x y z) DO SET %1=!%1:%%L=%%L!
goto :EOF

:done
