NFSv4.1 --> NFSv4.2 client implementation?

NFSv4.1 --> NFSv4.2 client implementation?

[Cedric Blancher]

Good morning!

What are the differences between NFSv4.1 and NFSv4.2 for a NFSv4
client, if we ignore server-side copy and READ_PLUS support?
Can a NFSv4.1 client then identify itself als NFSv4.2 client?

Ced
-- 
Cedric Blancher <cedric.blancher@gmail.com>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur

Re: NFSv4.1 --> NFSv4.2 client implementation?

[Jeff Layton]

On Sat, 2023-11-18 at 08:53 +0100, Cedric Blancher wrote:
> Good morning!
> 
> What are the differences between NFSv4.1 and NFSv4.2 for a NFSv4
> client, if we ignore server-side copy and READ_PLUS support?
> Can a NFSv4.1 client then identify itself als NFSv4.2 client?
> 

Yes. I believe that NFSv4.2 consists entirely of optional features over
NFSv4.1, so it's legitimate for a client or server to advertise itself
as a v4.2 capable, but support none of the features.

-- 
Jeff Layton <jlayton@kernel.org>

Re: NFSv4.1 --> NFSv4.2 client implementation?

[Cedric Blancher]

On Sat, 18 Nov 2023 at 13:01, Jeff Layton <jlayton@kernel.org> wrote:
>
> On Sat, 2023-11-18 at 08:53 +0100, Cedric Blancher wrote:
> > Good morning!
> >
> > What are the differences between NFSv4.1 and NFSv4.2 for a NFSv4
> > client, if we ignore server-side copy and READ_PLUS support?
> > Can a NFSv4.1 client then identify itself als NFSv4.2 client?
> >
>
> Yes. I believe that NFSv4.2 consists entirely of optional features over
> NFSv4.1, so it's legitimate for a client or server to advertise itself
> as a v4.2 capable, but support none of the features.

Can anyone confirm this? So NFSv4.2 does not require protocol minor
version negotiation, or how does it work?

Ced
-- 
Cedric Blancher <cedric.blancher@gmail.com>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur

Re: NFSv4.1 --> NFSv4.2 client implementation?

[Anna Schumaker]

Hi Ced,

On Sun, Nov 19, 2023 at 11:58 AM Cedric Blancher
<cedric.blancher@gmail.com> wrote:
>
> On Sat, 18 Nov 2023 at 13:01, Jeff Layton <jlayton@kernel.org> wrote:
> >
> > On Sat, 2023-11-18 at 08:53 +0100, Cedric Blancher wrote:
> > > Good morning!
> > >
> > > What are the differences between NFSv4.1 and NFSv4.2 for a NFSv4
> > > client, if we ignore server-side copy and READ_PLUS support?
> > > Can a NFSv4.1 client then identify itself als NFSv4.2 client?
> > >
> >
> > Yes. I believe that NFSv4.2 consists entirely of optional features over
> > NFSv4.1, so it's legitimate for a client or server to advertise itself
> > as a v4.2 capable, but support none of the features.
>
> Can anyone confirm this? So NFSv4.2 does not require protocol minor
> version negotiation, or how does it work?

I can confirm this. When mounting with NFS v4.2, the client will
detect if the server doesn't support one of the new operations (by the
server returning NFS4ERR_NOTSUPP) and will remember not to try it
again.

Anna

>
> Ced
> --
> Cedric Blancher <cedric.blancher@gmail.com>
> [https://plus.google.com/u/0/+CedricBlancher/]
> Institute Pasteur