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SubjectRe: Is netmask illegal?
On Sat, 11 Jan 1997, Eugene Kanter wrote:

> Quick one:
> kernel 2.0.27
> ifconfig eth0 netmask broadcast
> works fine.

Whoa.. it works fine? Do you mean, it accepts the netmask/broadcast
without complaining, or actually works for networking?

> kernel 2.1.20
> ifconfig eth0 netmask broadcast
> SIOCSIFNETMASK: Invalid argument
> What is wrong?

Unless the RFC's changed, this is illegal, isn't it? This results in 128
(formerly 126) networks of two numbers. But the first host number of each
network is reserved for the network address, and the last host of each
network is reserved for broadcast, right? If this is all still true, then
a 7-bit netmask is a no-no.

In any case, you wouldn't have the right broadcast, either. 255 would
only be used for hosts 254 and 255; host 97 would use

If I'm wrong on any of these, please correct me.

# B. James Phillippe # Network/System Administrator #
# <> # #
# Finger for PGP key # Enlightened since era 1.1.59 #

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