Path: csiph.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail
From: Andy Burns <usenet@andyburns.uk>
Newsgroups: comp.os.linux.misc
Subject: Re: Multi-Networking in Linux - Multiple Subnets
Date: Thu, 30 Jul 2026 15:06:12 +0100
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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 ...