def configure_callback(conf):
    """Receive configuration block"""
    global REDIS_HOST, REDIS_PORT, VERBOSE_LOGGING, QUEUE_NAMES
    for node in conf.children:
        if node.key == 'Host':
            REDIS_HOST = node.values[0]
        elif node.key == 'Port':
            REDIS_PORT = int(node.values[0])
        elif node.key == 'Verbose':
            VERBOSE_LOGGING = bool(node.values[0])
        elif node.key == 'Queues':
            QUEUE_NAMES = list(node.values)
        else:
            collectd.warning('redis_queues plugin: Unknown config key: %s.'
                             % node.key)
    log_verbose('Configured with host=%s, port=%s' % (REDIS_HOST, REDIS_PORT))
    for queue in QUEUE_NAMES:
        log_verbose('Watching queue %s' % queue)
    if not QUEUE_NAMES:
        log_verbose('Not watching any queues')