Re: ifconfig network resolution (Re: pointers to material for using netbook's wireless as access point)

[Joe]

On Sun, 11 Jun 2017 17:03:40 +0900
Joel Rees  wrote:

> On Sun, Jun 11, 2017 at 4:57 PM, Joe  wrote:

> >
> > I've seen this kind of behaviour a very long time ago, and I can't
> > really believe it is still happening, but...  
> 
> See the other sub-thread. But it does go to class C instead of the
> partial class C when the device address comes at the end of the list.
> 

OK, not what I saw then. I was bitten by a bit of system software
somewhere that treated the 10. network as class A regardless of
netmask. I never got to the bottom of it, but I never again used 10. as
anything other than class A. It was quite a few years ago.

-- 
Joe

Re: ifconfig network resolution (Re: pointers to material for using netbook's wireless as access point)

[Joel Rees]

On Sun, Jun 11, 2017 at 4:57 PM, Joe  wrote:
> On Sat, 10 Jun 2017 10:57:47 +0900
> Joel Rees  wrote:
>
>> Experimenting from the command line, I find myself puzzled about the
>> arguments for ifconfig.
>>
>> Reading the manual, it would appear that the arguments for ifconfig
>> should be something like this:
>>
>> ifconfig eth0 netmask 255.255.255.224 netmask 255.255.255.224
>> broadcast 10.19.23.223 10.19.23.94
>>
>> But the command returns with
>>
>> SIOCSIFNETMASK: Can't allocate this address.
>> SIOCSIFBRDADDR: Can't allocate this address.
>>
>> If I repeat the command, it gives no errors, but the netmask and
>> broadcast address end up full class A (255.0.0.0 and 10.255.255.255).
>>
>> Anyone have an idea what's happening?
>>
>
> Could you humour me for a moment, and try the exercise with one of the
> 192.168... networks, with the same sized subnet?
>
> I've seen this kind of behaviour a very long time ago, and I can't
> really believe it is still happening, but...

See the other sub-thread. But it does go to class C instead of the partial
class C when the device address comes at the end of the list.

--
Joel Rees

Trying to re-invent the entire industry all by myself:
http://defining-computers.blogspot.jp/

Re: ifconfig network resolution (Re: pointers to material for using netbook's wireless as access point)

[Joe]

On Sat, 10 Jun 2017 10:57:47 +0900
Joel Rees  wrote:

> Experimenting from the command line, I find myself puzzled about the
> arguments for ifconfig.
> 
> Reading the manual, it would appear that the arguments for ifconfig
> should be something like this:
> 
> ifconfig eth0 netmask 255.255.255.224 netmask 255.255.255.224
> broadcast 10.19.23.223 10.19.23.94
> 
> But the command returns with
> 
> SIOCSIFNETMASK: Can't allocate this address.
> SIOCSIFBRDADDR: Can't allocate this address.
> 
> If I repeat the command, it gives no errors, but the netmask and
> broadcast address end up full class A (255.0.0.0 and 10.255.255.255).
> 
> Anyone have an idea what's happening?
> 

Could you humour me for a moment, and try the exercise with one of the
192.168... networks, with the same sized subnet?

I've seen this kind of behaviour a very long time ago, and I can't
really believe it is still happening, but...

-- 
Joe

Re: ifconfig network resolution (Re: pointers to material for using netbook's wireless as access point)

[Joel Rees]

Sorry my typing is so lame.

On Sat, Jun 10, 2017 at 10:57 AM, Joel Rees  wrote:
> Experimenting from the command line, I find myself puzzled about the
> arguments for ifconfig.
>
> Reading the manual, it would appear that the arguments for ifconfig
> should be something like this:
>
> ifconfig eth0 netmask 255.255.255.224 netmask 255.255.255.224
> broadcast 10.19.23.223 10.19.23.94

   sudo ifconfig eth0 netmask 255.255.255.224 broadcast 10.19.23.223
10.19.23.194

> But the command returns with
>
> SIOCSIFNETMASK: Can't allocate this address.
> SIOCSIFBRDADDR: Can't allocate this address.
>
> If I repeat the command, it gives no errors, but the netmask and
> broadcast address end up full class A (255.0.0.0 and 10.255.255.255).

But if I repeat it often enough (with legitimate parameters), it seems to
decide to believe me, and sets the nic to the requested netmask and
broadcast address.

Once or twice may have been bad parameters, but I have just hit the
up arrow and it goes ahead and sets the parameters to what I said on
the second try.

> Anyone have an idea what's happening?

-- 
Joel Rees

One of these days I'll get someone to pay me
to design a language that combines the best of Forth and C.
Then I'll be able to leap wide instruction sets with a single #ifdef,
run faster than a speeding infinite loop with a #define,
and stop all integer size bugs with my bare cast.

More of my delusions:
http://reiisi.blogspot.com/2017/05/do-not-pay-modern-danegeld-ransomware.html
http://reiisi.blogspot.jp/p/novels-i-am-writing.html