[nfsv4] Possibility of adding additional REQUIRED attributes

[David Noveck <[e-mail]>]

IIRC, at an earlier interim(?) meeting you raised the issue of the possible
addition of other attributes to the set of *REQUIRED* attributes.   As I am
now updating rfc5661bis to reflect the attribute categorization changes
made in other documents including toe regarding mode, owner and
owner_group, I'd like to follow up on this issue soon,  if that is
possible.

Since I am looking to finalize a full reworking of attribute categorization
to appear in -03, I'd like to close out this discussion with regard to the
rfc5661bis effort, if it still has relevance to that effort.  To make
progress on this, I would need a list of attributes that you believe need
to be made *REQUIRED* as part of rfc5661bis. Right now, I don't
anticipating any, although in rewriting the general description of
*OPTIONAL* (formerly "RECOMMENDED") attributes, I am trying to provide a
more balanced discussion, getting rid of the text which stressed the
difficulty (for servers) of implementing attributes and underplayed the
issues for the client in doing without attributes typically expected.  I'm
also explicitly mentioning the need for OPTIONAL attributes in connection
with OPTIONAL features.

Although I don't know of any attributes that need to be made *REQUIRED *in
the context of fc5661bis, I feel that there are a number of attributes that
need to be considered for promotion in  NFSv4.3, now that it is in the
process of graduating from the snide remark stage to the initial discussion
stage.  These would include the ones you alluded to, the attributes brought
over from NFSv3, but I would also like us to include a substantial subset
of the per-fs *OPTIONAL *attributes.  Some examples:

   - fs_charset is very easy for the server to implement and making it
   *REQUIRED* avoid the added complexity for the client of dealing with the
   case of this attribute not being supported.
   - aclsupport raises similar issues even if it is associated with an
*OPTIONAL
   *feature.  This is similar to other attributes which provide
gateways to *OPTIONAL
   *features, with very simple implementations possible when the
*OPTIONAL *feature
   is not supported..
   - fs_layout_type could be made *REQUIRED* with servers not supporting
   pNFS simply returning a zero-length array.

Please update me regarding any issues you have regarding attributes in
rfc5661bis as soon as you can.  Also, I'd like us to schedule some
discussion of NFSv4.3 at a forthcoming interim meeting so we can really
kick off this effort.