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Re: etherconf or ifupdown problem with subnets



Michael Stone wrote:

> On Tue, Jul 16, 2002 at 11:31:03AM +0100, Scott James Remnant wrote:
> >The old classful network defaults are probably still the most sensible.
> 
> Absolutely not. I don't know of anyone who actually uses a "class A"
> range as a single broadcast network with 16M machines.
> 
True, but then has much of the old Class A range been used yet?

> >If you're arguing that the introduction of CIDR means that we should use
> >smaller defaults than the old ranges, then a /30 should be the default.
> 
> No! 
> 
Why not?

> >I can't see any argument for any other default range, /24 is far too big
> >for any real networks to be "useful".
> 
> Curious. I'm surrounded by /24's here. 
> 
Are they RFC1918 space, or CIDR space?

> But whatever. The point you seem to missing is that given an address and
> netmask, a sane broadcast address can be calculated in most cases.
> (Assuming 1's broadcast.) The default will fail in corner cases, but
> will usually make sense.
> 
Indeed I missed that point when reading your e-mail, sorry.  The kernel
should imo choose broadcast based on netmask if you give that, so yeah,
I agree :)

However, if you don't give a netmask either, I don't see why the old
classful defaults are wrong.

Scott
-- 
Scott James Remnant     Have you ever, ever felt like this?  Had strange
http://netsplit.com/      things happen?  Are you going round the twist?

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