Re: [patch -mm] net namespace: empty framework

[ebiederm@xmission.com (Eric W. Biederman)]

Cedric Le Goater <clg@fr.ibm.com> writes:

>> no problem here, but I think we will need another one,
>> or some smart way to do the network isolation (layer 3)
>> for the network namespace (as alternative to the layer 2
>> approach) ...
>
> My feeling (Dmitry and Daniel can correct me) is that it will be
> addressed with an unshare-like flag : NETNS2 and NETNS3.
>  
>> as they are both complementary in some way, I'm not sure
>> a single space will suffice ...
>
> hmm, so you think there could be a 2 differents namespaces
> for network to handle layer 2 or 3. Couldn't that be just a sub part
> of net_namespace.

The justification is performance and a little on the simplicity side.

My personal feel is still that layer 3 is something easier done
as a new kind of table in an iptables type infrastructure.  And in
fact I believe if done that way would capture do what 90%+ of what
all of the iptables rules do.  So it might be a nice firewalling speed up.

I don't think the layer 3 idea where you just do bind filter fits
the namespace concept very well.

Eric