2023-11-18 07:59:23

by Cedric Blancher

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

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 <[email protected]>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur


2023-11-18 12:03:07

by Jeffrey Layton

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

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 <[email protected]>

2023-11-19 16:58:48

by Cedric Blancher

[permalink] [raw]
Subject: Re: NFSv4.1 --> NFSv4.2 client implementation?

On Sat, 18 Nov 2023 at 13:01, Jeff Layton <[email protected]> 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 <[email protected]>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur

2023-11-19 17:21:04

by Anna Schumaker

[permalink] [raw]
Subject: Re: NFSv4.1 --> NFSv4.2 client implementation?

Hi Ced,

On Sun, Nov 19, 2023 at 11:58 AM Cedric Blancher
<[email protected]> wrote:
>
> On Sat, 18 Nov 2023 at 13:01, Jeff Layton <[email protected]> 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 <[email protected]>
> [https://plus.google.com/u/0/+CedricBlancher/]
> Institute Pasteur