[Observium] Auto discovery subnet

Hi,

I've added below line to config.php but when I run "discovery.php -h all" it doesn't try to use snmp to find hosts on 10.0.0.0/24

$config['autodiscovery']['ip_nets'] = array("127.0.0.0/8", "10.0.0.0/24"); // Networks to permit autodiscovery

What I'm doing wrong ?

Thanks

Dominik