Re: Is netmask 255.255.255.254 illigal?

Keith Owens (kaos@ocs.com.au)
Sun, 12 Jan 1997 16:49:46 +1100


On Sat, 11 Jan 1997 22:46:39 -0500 (EST),
Eugene Kanter <eugene@saturn.net> wrote:
>kernel 2.1.20
>
>ifconfig eth0 206.42.0.97 netmask 255.255.255.254 broadcast 206.42.0.255
>SIOCSIFNETMASK: Invalid argument
>
>What is wrong?
>
>Did I do something not right or it is kernel bug?

netmask 255.255.255.254 only leaves 1 bit host addresses. Since you
must have a network (all bits 0) and a broadcast address (all bits 1),
this leaves no room for hosts. 2.1.20 checks and rejects this. If you
really mean a broadcast address of 206.42.0.255 then your netmask
should be 255.255.255.0.