Invalid subnet masks

[Matt Churchyard]

> On 11 Feb 2015, at 17:38, Warren Block <wblock at wonkity.com> wrote:
> 
>> On Wed, 11 Feb 2015, Matt Churchyard wrote:
>> 
>> Just been helping someone on the forums who appears to have configured their network interface incorrectly. It looks like they've assigned 250.250.250.0 as the netmask.
>> I've tried assigning this netmask on a 10.1 machine and ifconfig happily accepts it.
> 
> As a tangent to that question, ifconfig(8) and the rc.conf settings do accept CIDR notation, which is both shorter and clearer than a dotted quad IP address and a separate netmask:
> 
> ifconfig em0 inet 192.168.1.1/24

Yeah I've been using that format in rc.conf for years. Quicker to type and looks tidy.