def ApplyChangesOnTheFly(timeout=90):
    count = 0
    status = ixNet.getAttribute('/globals/topology', '-applyOnTheFlyState')
    print 'Aplying changes on the fly:', status
    while status == "notAllowed":
        print "      {count}: /globals/topology -applyOnTheFlyState --> {status}".format(count=count, status=status)
        status = ixNet.getAttribute('/globals/topology', '-applyOnTheFlyState')
        time.sleep(1)
        count += 1
        if count > timeout:
            print "Waited for {count}".format(count=count)

    status = ixNet.getAttribute('/globals/topology', '-applyOnTheFlyState')
    if status == "allowed":
        ixNet.execute('applyOnTheFly', '/globals/topology')
        return 0
    elif status == "nothingToApply":
        ixNet.execute('applyOnTheFly', '/globals/topology')
        return 0
    else:
        print "Status unknown '$status'"
        return 1