Re: [PATCH nft v2 3/3] src: add xt compat support

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Fri, Apr 10, 2015 at 12:48:44AM +0100, Patrick McHardy wrote:
> On 10.04, Pablo Neira Ayuso wrote:
> > On Fri, Apr 10, 2015 at 12:21:06AM +0100, Patrick McHardy wrote:
> > > On 10.04, Pablo Neira Ayuso wrote:
> > > > On Thu, Apr 09, 2015 at 10:51:35PM +0200, Florian Westphal wrote:
> > > > > Why would I want to re-write a working nft+compat ruleset to one
> > > > > that only uses native expressions?
> > > > 
> > > > The fact is that we cannot push users to use nf_tables, but we can
> > > > provide good reasons to adopt the native replacements and tools to
> > > > migrate easily.
> > > 
> > > We actually can by translating their iptables ruleset transparently.
> > 
> > Users' ruleset can be very sophisticated, some of them may just not
> > move forward because only one single feature that they need is
> > missing. So they will postpone migration. That is not good.
> > 
> > The translation is a complementary thing, not a replacement of the
> > compatibility layer.
> 
> The difference is that the translation layer doesn't restrict us in
> future decisions, and this one does.

The user will run translation and will notice than some feature is
missing. Bad luck, he will retry months later. It will keep repeating
the process until it gets the features it needs. No matter how nice
nftables features are, because he still don't have access to what it
needs.

> And actually if you consider what the majority of users are, its people
> using distro provided firewalls, the translation layer will actually
> get us the huge majority of users.
>
> People who actively want to switch won't mind changing their ruleset,
> so they might as well tell us if some feature is missing and we can
> then discuss how to implement it in nftables.

They will tell us what they need, then they will sit down waiting
until distributors start packaging the new feature, which means
another wait of ~2 years. Most people rely on Linux distributions, not
bleeding edge kernels. You know how behind people can remain from
mainstream to feel -stable.