Re-exporting NFS shares with a generated fsid as a UUID?

Re-exporting NFS shares with a generated fsid as a UUID?

[James Pearson]

I've been experimenting with re-exporting NFS shares and using the 
external fsidd service via the 'reexport' option - which all seems to 
work OK

As it is possible to use a UUID as a fsid for an export, would it 
possible to allow an automatically generated fsid as a UUID - i.e. 
instead of talking to an external service to provide a fsid, just 
generate a UUID which would be a hash (of some kind) of the exported 
path ? i.e. no need to use an external database to supply a consistent 
fsid ?

Thanks

James Pearson

Re: Re-exporting NFS shares with a generated fsid as a UUID?

[Daire Byrne]

We just hard code "fsid=12345" into the /etc/exports for each
mountpoint on the "re-export" server. We use config management on our
servers to maintain consistency.

We also mostly use NFSv3 re-exports but that shouldn't matter much.

Things get a bit trickier in the case of something like a Netapp that
might have multiple "volumes" appear as a single namespace (you have
to fsid each one in the tree).

Daire


On Tue, 22 Jul 2025 at 09:49, James Pearson <jcpearson@gmail.com> wrote:
>
> I've been experimenting with re-exporting NFS shares and using the
> external fsidd service via the 'reexport' option - which all seems to
> work OK
>
> As it is possible to use a UUID as a fsid for an export, would it
> possible to allow an automatically generated fsid as a UUID - i.e.
> instead of talking to an external service to provide a fsid, just
> generate a UUID which would be a hash (of some kind) of the exported
> path ? i.e. no need to use an external database to supply a consistent
> fsid ?
>
> Thanks
>
> James Pearson
>
>

Re: Re-exporting NFS shares with a generated fsid as a UUID?

[James Pearson]

I'm using the reexport=auto-fsidnum option with crossmnt (as Netapp is 
involved) and using fsidd - as there could potentially be hundreds of 
child volumes - which all works well, but I was just wondering if 
instead of using an external service/database to map an export path to a 
fsid, would it be 'better' if that mapping could be done internally by 
creating a UUID hash of the export path?

Thanks

James Pearson

On 22/07/2025 12:36, Daire Byrne wrote:
> We just hard code "fsid=12345" into the /etc/exports for each
> mountpoint on the "re-export" server. We use config management on our
> servers to maintain consistency.
>
> We also mostly use NFSv3 re-exports but that shouldn't matter much.
>
> Things get a bit trickier in the case of something like a Netapp that
> might have multiple "volumes" appear as a single namespace (you have
> to fsid each one in the tree).
>
> Daire
>
>
> On Tue, 22 Jul 2025 at 09:49, James Pearson <jcpearson@gmail.com> wrote:
>> I've been experimenting with re-exporting NFS shares and using the
>> external fsidd service via the 'reexport' option - which all seems to
>> work OK
>>
>> As it is possible to use a UUID as a fsid for an export, would it
>> possible to allow an automatically generated fsid as a UUID - i.e.
>> instead of talking to an external service to provide a fsid, just
>> generate a UUID which would be a hash (of some kind) of the exported
>> path ? i.e. no need to use an external database to supply a consistent
>> fsid ?
>>
>> Thanks
>>
>> James Pearson
>>
>>