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Multi-Networking in Linux - Multiple Subnets

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  Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-29 23:23 -0400
    Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-30 04:14 +0000
      Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-30 23:38 -0400
        Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-31 05:31 +0000
        Re: Multi-Networking in Linux - Multiple Subnets Richard Kettlewell <invalid@invalid.invalid> - 2026-07-31 09:44 +0100
          Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 12:19 +0100
    Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-30 12:37 +0200
      Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 13:42 +0200
        Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-30 13:58 +0200
          Re: Multi-Networking in Linux - Multiple Subnets Robert Heller <heller@deepsoft.com> - 2026-07-30 12:14 +0000
            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:36 +0200
          Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-30 13:25 +0100
            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:37 +0200
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 18:43 +0200
            Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-30 19:22 +0000
              Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 21:53 +0200
                Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-31 05:08 +0000
                  Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-31 01:16 -0400
                    Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-31 08:00 +0000
              Re: Multi-Networking in Linux - Multiple Subnets Robert Heller <heller@deepsoft.com> - 2026-07-30 20:07 +0000
                Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-07-31 05:14 +0000
            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:38 +0200
              Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 12:46 +0100
                Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:57 +0200
              Re: Multi-Networking in Linux - Multiple Subnets - Movistar "docs" "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 14:25 +0200
          Re: Multi-Networking in Linux - Multiple Subnets Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-07-30 21:18 +0000
            Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-30 23:50 -0400
              Re: Multi-Networking in Linux - Multiple Subnets Robert Riches <spamtrap42@jacob21819.net> - 2026-07-31 04:06 +0000
                Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-31 00:34 -0400
                  Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:50 +0200
                    Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 14:51 +0200
                      Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 14:37 +0100
            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:43 +0200
              Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 12:50 +0100
                Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 14:00 +0200
              Re: Multi-Networking in Linux - Multiple Subnets Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-07-31 22:52 +0000
                Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-31 23:45 -0400
        Re: Multi-Networking in Linux - Multiple Subnets Robert Heller <heller@deepsoft.com> - 2026-07-30 11:59 +0000
          Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-30 13:32 +0100
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 18:44 +0200
            Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-30 18:06 +0100
              Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 21:54 +0200
          Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-30 23:48 -0400
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 08:15 +0200
            Re: Multi-Networking in Linux - Multiple Subnets Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-07-31 06:53 +0000
              Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 14:52 +0200
            Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 12:10 +0100
              Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 15:04 +0200
                Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 14:42 +0100
                  Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 16:24 +0200
          Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 14:04 +0200
            Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 15:06 +0200
              Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 14:42 +0100
                Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 16:25 +0200
                  Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 15:34 +0100
        Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-30 13:24 +0100
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 08:16 +0200
            Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-31 12:15 +0100
        Re: Multi-Networking in Linux - Multiple Subnets Andy Burns <usenet@andyburns.uk> - 2026-07-30 14:53 +0100
          Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-07-30 14:59 +0100
            Re: Multi-Networking in Linux - Multiple Subnets Andy Burns <usenet@andyburns.uk> - 2026-07-30 15:06 +0100
              Re: Multi-Networking in Linux - Multiple Subnets Rich <rich@example.invalid> - 2026-07-30 14:35 +0000
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 18:46 +0200
        Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-30 23:45 -0400
        Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 13:51 +0200
          Re: Multi-Networking in Linux - Multiple Subnets "Stanislav N. aka pztrn" <no@email.please> - 2026-07-31 17:28 +0500
          Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-31 15:07 +0200
          Re: Multi-Networking in Linux - Multiple Subnets Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-07-31 22:55 +0000
      Re: Multi-Networking in Linux - Multiple Subnets c186282 <c186282@nnada.net> - 2026-07-30 23:43 -0400
        Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-07-31 14:28 +0200
    Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-07-30 13:48 +0200

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#89255

On 30/07/2026 17:44, Marc Haber wrote:

> 
> 192.168.0.0/16 is NOT a class B network and has never been.
> 
technically, it is.

And always has been

Just conventional semantics has it that is a particular range


> Greetings
> Marc

-- 
You can get much farther with a kind word and a gun than you can with a 
kind word alone.

Al Capone

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#89269

The Natural Philosopher <tnp@invalid.invalid> wrote:
>On 30/07/2026 17:44, Marc Haber wrote:
>> 
>> 192.168.0.0/16 is NOT a class B network and has never been.
>> 
>technically, it is.
>
>And always has been

I could say okay, but then we'd both be wrong.

If you still regurgitate "knowledge" that became irrelevant three
decades ago, PLEASE regurgitate it correctly and remember that the
network class used to be selected by the first two bits of the IPv4
address.

I'm finished with this part of the discussion.

Greetings
Marc
-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89284

On 7/30/26 07:59, Robert Heller wrote:
> At Thu, 30 Jul 2026 13:42:04 +0200 Marc Haber <mh+usenetspam2616@zugschl.us> wrote:
> 
>>
>> "Carlos E. R." <robin_listas@es.invalid> wrote:
>>> eth0: flagsA63<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>>          inet 192.168.2.9  netmask 255.255.0.0  broadcast 192.168.255.255
>>
>> Using the entire 192.168.0.0/16 range for a single home network is a
>> sure sign of a person not knowing too much about networking or an
>> incompetent ISP.
> 
> Indeed.  If one really needs a class B sub-net for one's home netwoek (64K
> nodes?) I believe there are class B sub-nets under 172.16.0.0 to
> 172.31.255.255.  The 192.168.*.0 sub-nets are for class Class C Private
> sub-nets.

   I'm trying to ORGANIZE.

   I'd like to put all my "IOT"-type devices on
   their own subnet, but be able to easily GET
   at them.

   And for medium+ biz these days, 254 addresses
   may NOT be "good enough". Boxes, servers, printers,
   scanners, cams and such ... you CAN use up one
   subnet these days.

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#89303

Robert Heller <heller@deepsoft.com> wrote:
>At Thu, 30 Jul 2026 13:42:04 +0200 Marc Haber <mh+usenetspam2616@zugschl.us> wrote:
>
>> 
>> "Carlos E. R." <robin_listas@es.invalid> wrote:
>> >eth0: flagsA63<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>> >         inet 192.168.2.9  netmask 255.255.0.0  broadcast 192.168.255.255
>> 
>> Using the entire 192.168.0.0/16 range for a single home network is a
>> sure sign of a person not knowing too much about networking or an
>> incompetent ISP.
>
>Indeed.  If one really needs a class B sub-net for one's home netwoek (64K 
>nodes?) I believe there are class B sub-nets under 172.16.0.0 to 
>172.31.255.255.  The 192.168.*.0 sub-nets are for class Class C Private 
>sub-nets.

That was the case until classful IP addressing was replaced by
classless routing some 30 years ago. Since then people using the
"class X" terminology only divulge their outdated knowledge.

Greetings
Marc
-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89305

On Fri, 31 Jul 2026 08:15:15 +0200, Marc Haber wrote:

> That was the case until classful IP addressing was replaced by
> classless routing some 30 years ago. Since then people using the
> "class X" terminology only divulge their outdated knowledge.

Do we still do “Proxy ARP”?

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#89343

Lawrence D´Oliveiro <ldo@nz.invalid> wrote:
>On Fri, 31 Jul 2026 08:15:15 +0200, Marc Haber wrote:
>
>> That was the case until classful IP addressing was replaced by
>> classless routing some 30 years ago. Since then people using the
>> "class X" terminology only divulge their outdated knowledge.
>
>Do we still do “Proxy ARP”?

That is one technology that sohuld be avoided, but in some setups
(especially when trying to modernze/fix broken networks that were
installed with way too big networks - exactly what we're talking about
here), it is unavoidable.

I think I can count the situations where I had to use proxy arp with
the fingers of one hand.

Greetings
Marc
-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89312

On 31/07/2026 07:15, Marc Haber wrote:
> Since then people using the
> "class X" terminology only divulge their outdated knowledge.
> 
> Greetings

And you are merely demonstrating that whilst you know one little 
factoid, you are fucking ignorant about much else.

The  internet at large went classless because the BGP routers could 
handle the table sizes involved.

The class ABC terminology persisted as a neat way to refer to specific 
netmasks

And the private networkls of those sizes were defined to never be on a 
public network or routable by BGP

In the end its the usual mix of pedantry, technical issues and common 
speech.

https://datatracker.ietf.org/doc/html/rfc1918

RFC 1918 may be 30 years old, but it is still in effect. And it refers 
to classful networks


In a private network you can do WTF you like and have network spaces at 
any one bit boundary of a netmask . You can probably create even weirder 
netmasks than 2^n -1 boundaries, though only Farley Flud would try one.

Most people stick to the simple cases. And split into 'class C sized' 
subnets even in larger corporations because it limits the extent of 
broadcast floods. Even though switches already limit traffic between 
nodes to that which is desired only.

Carlos has a point. If Starlink restrict his router to a precise local 
IP and netmask, if he wants more he has no real option than to create 
some routable subnet .


-- 
“Ideas are inherently conservative. They yield not to the attack of 
other ideas but to the massive onslaught of circumstance"

    -  John K Galbraith

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#89344

The Natural Philosopher <tnp@invalid.invalid> wrote:
>The class ABC terminology persisted as a neat way to refer to specific 
>netmasks

Only in Idiots, the rests uses /8, /16 and /24.

>And the private networkls of those sizes were defined to never be on a 
>public network or routable by BGP

But noone with a sane grip on networking ever configures
192.168.0.0/16. You use a /24 network out of that range. And if you're
really smart, you pick a random third octet¹ to avoid conflicts.

>In the end its the usual mix of pedantry, technical issues and common 
>speech.
>
>https://datatracker.ietf.org/doc/html/rfc1918
>
>RFC 1918 may be 30 years old, but it is still in effect. And it refers 
>to classful networks

Of course it does, and it doees so correctly. 10.0.0.0/8 IS a class A
network, 172.16.0.0/12 IS a group of 16 class B network and
192.168.0.0/16 is a group of 256 class C networks. an IP address
belonging to a class is determined by the first bits. IP addresses
starting with binary 00 and 01 belong to Class A networks
(0.0.0.0-127.0.0.0), IP addresses starting with binary 10 belong to
class B networks (128.0.0.0-191.255.0.0), and IP addresses starting
with 110 belong to Class C networks (192.0.0.0-223.255.255.0). There
used to be a class D (beginning with 111), but thankfully noone
remembers that.

172.16.10.0/24 is not a class C network despite having a /24 netmask,
it's a /24 subnet of 172.16.0.0/16 which is a class B network.

|[8/5177]mh@swivel:~ $ ipcalc 172.16.10.0/24
|Address:   172.16.10.0          10101100.00010000.00001010. 00000000
|Netmask:   255.255.255.0 = 24   11111111.11111111.11111111. 00000000
|Wildcard:  0.0.0.255            00000000.00000000.00000000. 11111111
|=>
|Network:   172.16.10.0/24       10101100.00010000.00001010. 00000000
|HostMin:   172.16.10.1          10101100.00010000.00001010. 00000001
|HostMax:   172.16.10.254        10101100.00010000.00001010. 11111110
|Broadcast: 172.16.10.255        10101100.00010000.00001010. 11111111
|Hosts/Net: 254                   Class B, Private Internet
|
|[9/5178]mh@swivel:~ $ ipcalc 172.16.0.0/16
|Address:   172.16.0.0           10101100.00010000. 00000000.00000000
|Netmask:   255.255.0.0 = 16     11111111.11111111. 00000000.00000000
|Wildcard:  0.0.255.255          00000000.00000000. 11111111.11111111
|=>
|Network:   172.16.0.0/16        10101100.00010000. 00000000.00000000
|HostMin:   172.16.0.1           10101100.00010000. 00000000.00000001
|HostMax:   172.16.255.254       10101100.00010000. 11111111.11111110
|Broadcast: 172.16.255.255       10101100.00010000. 11111111.11111111
|Hosts/Net: 65534                 Class B, Private Interne

If you insist on using obsolete terminology, please at least get it
right.

>In a private network you can do WTF you like and have network spaces at 
>any one bit boundary of a netmask . You can probably create even weirder 
>netmasks than 2^n -1 boundaries, though only Farley Flud would try one.

Of course. I have a /23 network for historical reasons. When you
operate with public IPv4 addresses, you'll get quickly acquainted with
/27 through /30 networks.

>Most people stick to the simple cases. And split into 'class C sized' 
>subnets even in larger corporations because it limits the extent of 
>broadcast floods. Even though switches already limit traffic between 
>nodes to that which is desired only.

You even should split smaller. Many companies have been so careless
with the RFC1918 address space that they've run out of those
addresses.

On my network, I have /24 as network size, and I have like 16 of them.
I was too lazy to use /26 or /26 networks which would have been a more
sensible size.

>Carlos has a point. If Starlink restrict his router to a precise local 
>IP and netmask, if he wants more he has no real option than to create 
>some routable subnet .

It is still stupid to use such a HUGE network.

Greetings
Marc
-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89351

On 31/07/2026 14:04, Marc Haber wrote:
> The Natural Philosopher <tnp@invalid.invalid> wrote:
>> The class ABC terminology persisted as a neat way to refer to specific
>> netmasks
> 
> Only in Idiots, the rests uses /8, /16 and /24.
> 
>> And the private networkls of those sizes were defined to never be on a
>> public network or routable by BGP
> 
> But noone with a sane grip on networking ever configures
> 192.168.0.0/16. 

Why not. That's 'classless routing' you so endorse.
Or they might do /23 just to be different


You use a /24 network out of that range. And if you're
> really smart, you pick a random third octet¹ to avoid conflicts.
> 
Do I? Ought I? Should I? But classless routing says I do WTF I want.

>> In the end its the usual mix of pedantry, technical issues and common
>> speech.
>>
>> https://datatracker.ietf.org/doc/html/rfc1918
>>
>> RFC 1918 may be 30 years old, but it is still in effect. And it refers
>> to classful networks
> 
> Of course it does, and it doees so correctly. 10.0.0.0/8 IS a class A
> network, 172.16.0.0/12 IS a group of 16 class B network and
> 192.168.0.0/16 is a group of 256 class C networks. an IP address
> belonging to a class is determined by the first bits. IP addresses
> starting with binary 00 and 01 belong to Class A networks
> (0.0.0.0-127.0.0.0), IP addresses starting with binary 10 belong to
> class B networks (128.0.0.0-191.255.0.0), and IP addresses starting
> with 110 belong to Class C networks (192.0.0.0-223.255.255.0). There
> used to be a class D (beginning with 111), but thankfully noone
> remembers that.
But you said there is no such thing as class A B or C, it's all classless..

Frankly arguing with you is pointless. You contradict yourself at every 
paragraph
>
> Marc

-- 
There is something fascinating about science. One gets such wholesale 
returns of conjecture out of such a trifling investment of fact.

Mark Twain

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#89354

The Natural Philosopher <tnp@invalid.invalid> wrote:
>On 31/07/2026 14:04, Marc Haber wrote:
>> really smart, you pick a random third octet¹ to avoid conflicts.
>> 
>Do I? Ought I? Should I? But classless routing says I do WTF I want.

everybody uses 192.168.0.0/24 or 192.168.1.0/24. Deutsche Telekom
Routers use 192.168.2.0/24. Fritzboxes use 192.168.178.0/24. I'd avoid
all of these and maybe the "easy" or "nice" numbers as 100, 200, 254,
250, 128, 192, 64, 42, 23.

You'll be happy about that once you begin building VPNs to your
friends.

But of course you're free to ignore 30 years of IP networking
experience that was sometimes painful to build. I made a couple
mistakes myself.

>> Of course it does, and it doees so correctly. 10.0.0.0/8 IS a class A
>> network, 172.16.0.0/12 IS a group of 16 class B network and
>> 192.168.0.0/16 is a group of 256 class C networks. an IP address
>> belonging to a class is determined by the first bits. IP addresses
>> starting with binary 00 and 01 belong to Class A networks
>> (0.0.0.0-127.0.0.0), IP addresses starting with binary 10 belong to
>> class B networks (128.0.0.0-191.255.0.0), and IP addresses starting
>> with 110 belong to Class C networks (192.0.0.0-223.255.255.0). There
>> used to be a class D (beginning with 111), but thankfully noone
>> remembers that.
>But you said there is no such thing as class A B or C, it's all classless..

It's all classless on today's Internet. I gave you a free history
lesson.

>Frankly arguing with you is pointless. You contradict yourself at every 
>paragraph

and you're wrong.

-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89334

On 2026-07-30 13:59, Robert Heller wrote:
> At Thu, 30 Jul 2026 13:42:04 +0200 Marc Haber <mh+usenetspam2616@zugschl.us> wrote:
> 
>>
>> "Carlos E. R." <robin_listas@es.invalid> wrote:
>>> eth0: flagsA63<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>>          inet 192.168.2.9  netmask 255.255.0.0  broadcast 192.168.255.255
>>
>> Using the entire 192.168.0.0/16 range for a single home network is a
>> sure sign of a person not knowing too much about networking or an
>> incompetent ISP.
> 
> Indeed.  If one really needs a class B sub-net for one's home netwoek (64K
> nodes?) I believe there are class B sub-nets under 172.16.0.0 to
> 172.31.255.255. 

Which I can not use. That modification to the ISP router will render it not working.

> The 192.168.*.0 sub-nets are for class Class C Private
> sub-nets.

LOL. ChatGPT just said to me:

The IPv4 address ranges reserved for private local networks (defined in RFC 1918) are:

| Private range                     | CIDR notation    | Number of addresses | Common use                                      |
| --------------------------------- | ---------------- | ------------------: | ----------------------------------------------- |
| **10.0.0.0 – 10.255.255.255**     | `10.0.0.0/8`     |          16,777,216 | Large enterprise networks, cloud infrastructure |
| **172.16.0.0 – 172.31.255.255**   | `172.16.0.0/12`  |           1,048,576 | Medium to large private networks                |
| **192.168.0.0 – 192.168.255.255** | `192.168.0.0/16` |              65,536 | Home routers and small office networks          |

It gives no link for this information, except citing RFC 1918

-- 
Cheers,
        Carlos E.R.
        ES🇪🇸, EU🇪🇺;

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#89345

"Carlos E. R." <robin_listas@es.invalid> wrote:
>On 2026-07-30 13:59, Robert Heller wrote:
>> The 192.168.*.0 sub-nets are for class Class C Private
>> sub-nets.
>
>LOL. ChatGPT just said to me:
>
>The IPv4 address ranges reserved for private local networks (defined in RFC 1918) are:
>
>| Private range                     | CIDR notation    | Number of addresses | Common use                                      |
>| --------------------------------- | ---------------- | ------------------: | ----------------------------------------------- |
>| **10.0.0.0 – 10.255.255.255**     | `10.0.0.0/8`     |          16,777,216 | Large enterprise networks, cloud infrastructure |
>| **172.16.0.0 – 172.31.255.255**   | `172.16.0.0/12`  |           1,048,576 | Medium to large private networks                |
>| **192.168.0.0 – 192.168.255.255** | `192.168.0.0/16` |              65,536 | Home routers and small office networks          |
>
>It gives no link for this information, except citing RFC 1918

That is not a contradiction. There is no obligation to waste IP
addresses, you can always choose a longer prefix. And it is actually a
smart idea to do so.

The fact that the net is full of incorrect, obsolete, and misleading
terminology is a reason for "AI" to ingest that and of course to
regurgitate it.

Greetings
Marc
-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89352

On 31/07/2026 14:06, Marc Haber wrote:
> "Carlos E. R." <robin_listas@es.invalid> wrote:
>> On 2026-07-30 13:59, Robert Heller wrote:
>>> The 192.168.*.0 sub-nets are for class Class C Private
>>> sub-nets.
>>
>> LOL. ChatGPT just said to me:
>>
>> The IPv4 address ranges reserved for private local networks (defined in RFC 1918) are:
>>
>> | Private range                     | CIDR notation    | Number of addresses | Common use                                      |
>> | --------------------------------- | ---------------- | ------------------: | ----------------------------------------------- |
>> | **10.0.0.0 – 10.255.255.255**     | `10.0.0.0/8`     |          16,777,216 | Large enterprise networks, cloud infrastructure |
>> | **172.16.0.0 – 172.31.255.255**   | `172.16.0.0/12`  |           1,048,576 | Medium to large private networks                |
>> | **192.168.0.0 – 192.168.255.255** | `192.168.0.0/16` |              65,536 | Home routers and small office networks          |
>>
>> It gives no link for this information, except citing RFC 1918
> 
> That is not a contradiction. There is no obligation to waste IP
> addresses, you can always choose a longer prefix. And it is actually a
> smart idea to do so.
> 
> The fact that the net is full of incorrect, obsolete, and misleading
> terminology is a reason for "AI" to ingest that and of course to
> regurgitate it.
> 
That is simply RFC1918.

Make up your mind

> Greetings
> Marc

-- 
"And if the blind lead the blind, both shall fall into the ditch".

Gospel of St. Mathew 15:14

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#89355

The Natural Philosopher <tnp@invalid.invalid> wrote:
>That is simply RFC1918.
>
>Make up your mind

Never argue with idiots. Dance a bit for me please.

-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89356

On 31/07/2026 15:25, Marc Haber wrote:
> The Natural Philosopher <tnp@invalid.invalid> wrote:
>> That is simply RFC1918.
>>
>> Make up your mind
> 
> Never argue with idiots. 
I just gave up

Dance a bit for me please.
There. Happy now?

> 

-- 
Those who want slavery should have the grace to name it by its proper 
name. They must face the full meaning of that which they are advocating 
or condoning; the full, exact, specific meaning of collectivism, of its 
logical implications, of the principles upon which it is based, and of 
the ultimate consequences to which these principles will lead. They must 
face it, then decide whether this is what they want or not.

Ayn Rand.

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#89240

On 30/07/2026 12:42, Marc Haber wrote:
> "Carlos E. R." <robin_listas@es.invalid> wrote:
>> eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>          inet 192.168.2.9  netmask 255.255.0.0  broadcast 192.168.255.255
> 
> Using the entire 192.168.0.0/16 range for a single home network is a
> sure sign of a person not knowing too much about networking or an
> incompetent ISP.
> 
+1

>> Works for me as above :-)
> 
> Until the moment you'd want to connect to another network.
> 
Inter subnet routing is supported by linux and many routers


> Greetings
> Marc

-- 
There is something fascinating about science. One gets such wholesale 
returns of conjecture out of such a trifling investment of fact.

Mark Twain

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#89304

The Natural Philosopher <tnp@invalid.invalid> wrote:
>On 30/07/2026 12:42, Marc Haber wrote:
>> "Carlos E. R." <robin_listas@es.invalid> wrote:
>>> Works for me as above :-)
>> 
>> Until the moment you'd want to connect to another network.
>> 
>Inter subnet routing is supported by linux and many routers

It is still a very bad idea.

-- 
----------------------------------------------------------------------------
Marc Haber         |   " Questions are the         | Mailadresse im Header
Rhein-Neckar, DE   |     Beginning of Wisdom "     | 
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 6224 1600402

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#89313

On 31/07/2026 07:16, Marc Haber wrote:
> The Natural Philosopher <tnp@invalid.invalid> wrote:
>> On 30/07/2026 12:42, Marc Haber wrote:
>>> "Carlos E. R." <robin_listas@es.invalid> wrote:
>>>> Works for me as above :-)
>>>
>>> Until the moment you'd want to connect to another network.
>>>
>> Inter subnet routing is supported by linux and many routers
> 
> It is still a very bad idea.
> 
Dont be silly.

What else is a router for? - a real one, not these consumer things. 
Routing between subnets using some kind of routing protocol. In the case 
of local stuff, static routers, For large organisations probably OSPF. 
In the big wide world Where There Be Tygers, BGP.
For end user speeds a Linux box with two nics (or only one) is a 
perfectly adequate router.


-- 
"It was a lot more fun being 20 in the 70's that it is being 70 in the 20's"
Joew Walsh

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#89243

Marc Haber wrote:

> Carlos E. R. wrote:
> >> eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>          inet 192.168.2.9  netmask 255.255.0.0  broadcast 192.168.255.255
> 
> Using the entire 192.168.0.0/16 range for a single home network is a
> sure sign of a person not knowing too much about networking or an
> incompetent ISP.
> 
>> Works for me as above :-)
> 
> Until the moment you'd want to connect to another network.
If you want multiple IP subnets on a single ethernet network, you'd be 
better off using VLANs, even cheapo switches can handle that, then your 
linux box with a single NIC can have VLAN sub-interfaces e.g. eth1.1 on 
192.168.0.1/24 and eth1.10 on 192.168.1.0/24

If you don't want VLANs you *could* use a NIC alias so that e.g. eth1 is 
on 192.168.0.1/24 and the alias eth1:2 is on 192.168.1.1/24 ... but why?

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#89244

On 30/07/2026 14:53, Andy Burns wrote:
> Marc Haber wrote:
> 
>> Carlos E. R. wrote:
>> >> eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
>>>          inet 192.168.2.9  netmask 255.255.0.0  broadcast 
>>> 192.168.255.255
>>
>> Using the entire 192.168.0.0/16 range for a single home network is a
>> sure sign of a person not knowing too much about networking or an
>> incompetent ISP.
>>
>>> Works for me as above :-)
>>
>> Until the moment you'd want to connect to another network.
> If you want multiple IP subnets on a single ethernet network, you'd be 
> better off using VLANs, even cheapo switches can handle that, then your 
> linux box with a single NIC can have VLAN sub-interfaces e.g. eth1.1 on 
> 192.168.0.1/24 and eth1.10 on 192.168.1.0/24
> 
> If you don't want VLANs you *could* use a NIC alias so that e.g. eth1 is 
> on 192.168.0.1/24 and the alias eth1:2 is on 192.168.1.1/24 ... but why?
> 
> 
They look the same to me.


-- 
The difference bweteen a psychopath and a saint is that the psychpoath 
takes what he can and gives only what he must, but the saint gives 
everything he can and takes only what he needs.

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