Re: [PATCH net-next 2/2] selftest: net: add icmp reply address test

[David Ahern <dsahern@gmail.com>]

On 11/2/19 4:08 PM, Francesco Ruggeri wrote:
>>>> I apologize in advance  for being slow ...
>>>> I have 3 namespaces that have to share the same LAN, I am not trying
>>>> 1-1 connections among those namespaces.
>>>>
>>>
>>> How would you cable this if it were an actual network with physical nodes?
>>> - bridge on R1 (since it is the gw for H1), with connections to R2 and
>>> H1 into the bridge
>>> - second connection between R1 and R2
>>> - connection between R2 and H2
>>>
>>> For the simulation, network namespaces represent physical nodes, veth
>>> pairs act like a cable between the nodes / namespaces and the bridge
>>> makes the LAN.
> 
> Thanks, I see what you mean now.
> I was assuming a different physical model, with all the namespaces on the LAN
> connected to a hub (simulated by the dummy device). For simulation purposes this
> model seem simpler: there are N interfaces instead of N pairs, and one does not
> have to deal with the bridge end of the pairs.
> Why is the model you described preferable?
> 

The tests are about traceroute in modern networks, not broadcast
domains. As such, it is preferable for these tests to be constructed
similar to other extisting networking tests.