Subject: Re: Connection tracking and vlan

From: Patrick McHardy <[email-masked]>
Date: Fri, 30 Oct 2009 17:26:11 +0100

Eric Dumazet wrote:
> Herbert Xu a écrit :
>> Adayadil Thomas <[email-masked]> wrote:
>>> If two connections have same 5 tuple, src ip, dst ip, src port, dst
>>> port, protocol(tcp/udp)
>>> but on different vlans (different vlan id), does the conntrack separate these ?
>> Probably not.  Patrick, can you confirm this?

Yes, you are right.

> Very strange, this question about vlan looks like discussion we had
> yesterday (or the day before...) about interfaces (versus packet defragmentation)

Indeed, we did have that discussion a couple of years ago. IIRC
Rusty also suggested to add the interface to the defragmentation
key to avoid having fragments from different interfaces being
reassembled since iptables interface matches will only match on
the interface of the first fragment.