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Groups > comp.os.linux.misc > #89224 > unrolled thread

Multi-Networking in Linux - Multiple Subnets

Started byc186282 <c186282@nnada.net>
First post2026-07-29 23:23 -0400
Last post2026-07-30 13:48 +0200
Articles 20 on this page of 86 — 13 participants

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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> - 2026-08-01 14:11 +0200
                        Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-01 16:49 +0200
                          Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-08-01 16:49 +0100
                            Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-08-01 19:14 +0000
                            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-08-01 22:57 +0200
            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 Richard Kettlewell <invalid@invalid.invalid> - 2026-08-01 12:22 +0100
                  Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-08-01 14:15 +0200
                    Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-08-01 14:09 +0100
                  Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-08-01 14:08 +0100
                    Re: Multi-Networking in Linux - Multiple Subnets rbowman <bowman@montana.com> - 2026-08-01 19:11 +0000
        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 Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2026-08-01 15:49 +0300
            Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-08-01 15:16 +0200
              Re: Multi-Networking in Linux - Multiple Subnets Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-01 16:52 +0200
                Re: Multi-Networking in Linux - Multiple Subnets The Natural Philosopher <tnp@invalid.invalid> - 2026-08-01 16:52 +0100
                  Re: Multi-Networking in Linux - Multiple Subnets "Carlos E. R." <robin_listas@es.invalid> - 2026-08-01 23:04 +0200
      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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#89334

From"Carlos E. R." <robin_listas@es.invalid>
Date2026-07-31 14:04 +0200
Message-ID<nd3halFi6v5U5@mid.individual.net>
In reply to#89238
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

FromMarc Haber <mh+usenetspam2616@zugschl.us>
Date2026-07-31 15:06 +0200
Message-ID<114i6ko$23rqe$1@news1.tnib.de>
In reply to#89334
"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

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-07-31 14:42 +0100
Message-ID<114i8or$2ols3$5@dont-email.me>
In reply to#89345
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

FromMarc Haber <mh+usenetspam2616@zugschl.us>
Date2026-07-31 16:25 +0200
Message-ID<114ib89$244va$1@news1.tnib.de>
In reply to#89352
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

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-07-31 15:34 +0100
Message-ID<114ibq0$2q6o1$1@dont-email.me>
In reply to#89355
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

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-07-30 13:24 +0100
Message-ID<114ffpq$1orc7$4@dont-email.me>
In reply to#89235
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

FromMarc Haber <mh+usenetspam2616@zugschl.us>
Date2026-07-31 08:16 +0200
Message-ID<114hej6$22b5l$1@news1.tnib.de>
In reply to#89240
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

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-07-31 12:15 +0100
Message-ID<114i044$2ktba$3@dont-email.me>
In reply to#89304
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

FromAndy Burns <usenet@andyburns.uk>
Date2026-07-30 14:53 +0100
Message-ID<nd13akF74rsU1@mid.individual.net>
In reply to#89235
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

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-07-30 14:59 +0100
Message-ID<114flbe$1qul5$4@dont-email.me>
In reply to#89243
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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#89245

FromAndy Burns <usenet@andyburns.uk>
Date2026-07-30 15:06 +0100
Message-ID<nd141oF784qU1@mid.individual.net>
In reply to#89244
The Natural Philosopher wrote:

> Andy Burns wrote:
>
>> 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.
Sure the names of the interfaces are just one character different (a 
colon vs a fullstop) but with VLANs, each sub-interface will keep its 
traffic isolated, won't see broadcast/multicast traffic from the other 
one ...

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#89246

FromRich <rich@example.invalid>
Date2026-07-30 14:35 +0000
Message-ID<114fnf6$1rmhf$2@dont-email.me>
In reply to#89245
Andy Burns <usenet@andyburns.uk> wrote:
> The Natural Philosopher wrote:
> 
>> Andy Burns wrote:
>>
>>> 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.
> Sure the names of the interfaces are just one character different (a 
> colon vs a fullstop) but with VLANs, each sub-interface will keep its 
> traffic isolated, won't see broadcast/multicast traffic from the other 
> one ...

True, but keep in mind that each physical interface still sees every 
packet that flows over the wire.  If any one of them are flipped to 
promiscious mode, that physical interface can capture everything, 
whether there are vlan's or not at the logical level.

So don't rely on VLAN's in an environment where you don't know/have 
control over all the connected endpoints.

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#89253

FromMarc Haber <mh+usenetspam2616@zugschl.us>
Date2026-07-30 18:46 +0200
Message-ID<114fv5b$1v1v5$1@news1.tnib.de>
In reply to#89243
Andy Burns <usenet@andyburns.uk> wrote:
>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

Please don't introduce VLANs unless you have fully understood how IP
routing works.

>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?

NIC aliases have been obsolete in Linux for 20 years. Since then, you
just configure a second address on the Interface.

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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#89283

Fromc186282 <c186282@nnada.net>
Date2026-07-30 23:45 -0400
Message-ID<tbicncVMNbf7h_H3nZ2dnZfqnPgAAAAA@giganews.com>
In reply to#89235
On 7/30/26 07:42, 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.
> 
>> Works for me as above :-)
> 
> Until the moment you'd want to connect to another network.

   Now you have me worried :-)

   I know that In Theory what I want can be
   done. My main goal is to move all my "IOT"
   type devices to a completely different
   subnet yet be able to get AT them as
   seamlessly as anything on the primary.

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#89330

From"Carlos E. R." <robin_listas@es.invalid>
Date2026-07-31 13:51 +0200
Message-ID<nd3gikFi6v2U4@mid.individual.net>
In reply to#89235
On 2026-07-30 13:42, 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.
> 
>> Works for me as above :-)
> 
> Until the moment you'd want to connect to another network.



LOL. I asked just now ChatGPT for the ranges, and it said:

| 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          |

Notice the last line... :-D

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

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#89338

From"Stanislav N. aka pztrn" <no@email.please>
Date2026-07-31 17:28 +0500
Message-ID<114i4dv$2n8go$1@dont-email.me>
In reply to#89330
31.07.2026 16:51, Carlos E. R. wrote:
> On 2026-07-30 13:42, 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.
>>
>>> Works for me as above :-)
>>
>> Until the moment you'd want to connect to another network.
> 
> 
> 
> LOL. I asked just now ChatGPT for the ranges, and it said:
> 
> | 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          |
> 
> Notice the last line... :-D
> 
That's why everyone should do CLASSLESS routing, not CLASSFUL :) CIDRs 
are your best friends.

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#89346

FromMarc Haber <mh+usenetspam2616@zugschl.us>
Date2026-07-31 15:07 +0200
Message-ID<114i6ln$23rrc$1@news1.tnib.de>
In reply to#89330
"Carlos E. R." <robin_listas@es.invalid> wrote:
>On 2026-07-30 13:42, 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.
>> 
>>> Works for me as above :-)
>> 
>> Until the moment you'd want to connect to another network.
>
>
>
>LOL. I asked just now ChatGPT for the ranges, and it said:
>
>| 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          |
>
>Notice the last line... :-D

Yes, we all know that you didn't understand things yet.

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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#89371

FromLawrence D’Oliveiro <ldo@nz.invalid>
Date2026-07-31 22:55 +0000
Message-ID<114j95c$34k3s$4@dont-email.me>
In reply to#89330
On Fri, 31 Jul 2026 13:51:48 +0200, Carlos E. R. wrote:

> I asked just now ChatGPT for the ranges, and it said:
> 
> | 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          |
> 
> Notice the last line... :-D

Did it tell you what happens if you use the wrong one?

Like I am using the wrong one; do you think ChatGPT will come for me?

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#89386

FromTauno Voipio <tauno.voipio@notused.fi.invalid>
Date2026-08-01 15:49 +0300
Message-ID<114kq1d$3joo1$1@dont-email.me>
In reply to#89330
On 31.7.2026 14.51, Carlos E. R. wrote:
> On 2026-07-30 13:42, 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.
>>
>>> Works for me as above :-)
>>
>> Until the moment you'd want to connect to another network.
> 
> 
> 
> LOL. I asked just now ChatGPT for the ranges, and it said:
> 
> | 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          |
> 
> Notice the last line... :-D
> 

Specifications for those address ranges are in RFC1918.

-- 

-TV

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#89391

From"Carlos E. R." <robin_listas@es.invalid>
Date2026-08-01 15:16 +0200
Message-ID<nd69sgF4quU3@mid.individual.net>
In reply to#89386
On 2026-08-01 14:49, Tauno Voipio wrote:
> On 31.7.2026 14.51, Carlos E. R. wrote:
>> On 2026-07-30 13:42, 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.
>>>
>>>> Works for me as above :-)
>>>
>>> Until the moment you'd want to connect to another network.
>>
>>
>>
>> LOL. I asked just now ChatGPT for the ranges, and it said:
>>
>> | 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          |
>>
>> Notice the last line... :-D
>>
> 
> Specifications for those address ranges are in RFC1918.

Yes, ChatGPT is citing that document.

The most commonly used private IPv4 address ranges are defined by Internet Engineering Task Force in RFC 1918:

| CIDR             | Address Range                     | Number of Addresses |
| ---------------- | --------------------------------- | ------------------- |
| `10.0.0.0/8`     | `10.0.0.0` – `10.255.255.255`     | 16,777,216          |
| `172.16.0.0/12`  | `172.16.0.0` – `172.31.255.255`   | 1,048,576           |
| `192.168.0.0/16` | `192.168.0.0` – `192.168.255.255` | 65,536              |


> 
I looked at the document itself on https://datatracker.ietf.org/doc/html/rfc1918:

3. Private Address Space

    The Internet Assigned Numbers Authority (IANA) has reserved the
    following three blocks of the IP address space for private internets:

      10.0.0.0        -   10.255.255.255  (10/8 prefix)
      172.16.0.0      -   172.31.255.255  (172.16/12 prefix)
      192.168.0.0     -   192.168.255.255 (192.168/16 prefix)

    We will refer to the first block as "24-bit block", the second as
    "20-bit block", and to the third as "16-bit" block. Note that (in
    pre-CIDR notation) the first block is nothing but a single class A
    network number, while the second block is a set of 16 contiguous
    class B network numbers, and third block is a set of 256 contiguous
    class C network numbers.

So, stop saying that `192.168.0.0/16` is wrong, or that 172.16/12 is wrong.


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

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