Re: LAYOUT4_NFSV4_1_FILES supported? Re: Can the PNFS blocklayout of the Linux nfsd server be used in a production environment?

["Chuck Lever" <cel@kernel.org>]

On Fri, Nov 28, 2025, at 3:57 AM, Sebastian Feld wrote:
> On Thu, Nov 27, 2025 at 5:41 PM Chuck Lever <cel@kernel.org> wrote:
>>
>> On Wed, Nov 26, 2025, at 9:14 PM, Zhou Jifeng wrote:
>> > Hello everyone, I learned through ChatGPT that the PNFS blocklayout of Linux
>> > nfsd cannot be used for production environment deployment. However, I saw
>> > a technical sharing conference video on YouTube titled "SNIA SDC 2024 - The
>> > Linux NFS Server in 2024" where it was mentioned that the PNFS blocklayout
>> > of nfsd has been fully maintained, which is contrary to the result given by
>> > ChatGPT.
>> >
>> > My question is: Can the PNFS blocklayout of nfsd be used for
>> > production environment deployment? If yes, from which kernel version can it
>> > be used in the production environment?
>>
>> Responding as the presenter of the SNIA SDC talk:
>>
>> There's a difference between "maintained" and "can be deployed in a
>> production environment". "Maintained" means there are developers
>> who are active and can help with bugs and new features. "Production
>> ready" means you can trust it with significant workloads.
>>
>> The pNFS block layout type has several subtypes. Pure block, iSCSI,
>> SCSI, and NVMe.
>
> What about the LAYOUT4_NFSV4_1_FILES layout type? Is that still supported?

Above, we're talking about the Linux NFS server... IIRC NFSD never
supported the NFSv4.1 file layout type. It has a simple experimental
implementation of the flexfile layout type (the MDS and DS are the
same server).

The Linux NFS client fully implements the file, flexfile, and all
the block layout types.


-- 
Chuck Lever