rfc9754.original.xml   rfc9754.xml 
<?xml version='1.0' encoding='utf-8'?> <?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE rfc SYSTEM "rfc2629-xhtml.ent">
<?xml-stylesheet type="text/xsl" href="rfc2629.xslt"?>
<rfc <!DOCTYPE rfc [
category="std" <!ENTITY nbsp "&#160;">
docName="draft-ietf-nfsv4-delstid-08" <!ENTITY zwsp "&#8203;">
ipr="trust200902" <!ENTITY nbhy "&#8209;">
obsoletes="" <!ENTITY wj "&#8288;">
scripts="Common,Latin" ]>
sortRefs="true" <rfc xmlns:xi="http://www.w3.org/2001/XInclude" category="std" docName="draft-ie
submissionType="IETF" tf-nfsv4-delstid-08" number="9754" ipr="trust200902" obsoletes="" updates="" sor
symRefs="true" tRefs="true" submissionType="IETF" consensus="true" symRefs="true" tocDepth="3"
tocDepth="3" tocInclude="true" version="3" xml:lang="en">
tocInclude="true"
version="3"
xml:lang="en">
<front> <front>
<title abbrev="Deleg Stateid"> <title abbrev="Delegation of Stateids">Extensions for Opening and Delegating F
Extending the Opening of Files in NFSv4.2 iles in NFSv4.2</title>
</title> <seriesInfo name="RFC" value="9754"/>
<seriesInfo name="Internet-Draft" value="draft-ietf-nfsv4-delstid-08"/>
<author fullname="Thomas Haynes" initials="T." surname="Haynes"> <author fullname="Thomas Haynes" initials="T." surname="Haynes">
<organization abbrev="Hammerspace">Hammerspace</organization> <organization abbrev="Hammerspace">Hammerspace</organization>
<address> <address>
<email>loghyr@hammerspace.com</email> <email>loghyr@hammerspace.com</email>
</address> </address>
</author> </author>
<author fullname="Trond Myklebust" initials="T." surname="Myklebust"> <author fullname="Trond Myklebust" initials="T." surname="Myklebust">
<organization abbrev="Hammerspace">Hammerspace</organization> <organization abbrev="Hammerspace">Hammerspace</organization>
<address> <address>
<email>trondmy@hammerspace.com</email> <email>trondmy@hammerspace.com</email>
</address> </address>
</author> </author>
<date year="2024" month="October" day="02"/> <date year="2025" month="March"/>
<area>Transport</area> <area>WIT</area>
<workgroup>Network File System Version 4</workgroup> <workgroup>nfsv4</workgroup>
<keyword>NFSv4</keyword> <keyword>NFSv4</keyword>
<abstract> <abstract>
<t> <t>
The Network File System v4 (NFSv4) allows a client to both open a The Network File System v4 (NFSv4) allows a client to both open a
file and be granted a delegation of that file. This delegation file and be granted a delegation of that file. This delegation
provides the client the right to authoritatively cache metadata provides the client the right to authoritatively cache metadata
on the file locally. This document presents several extensions on the file locally. This document presents several extensions
for both the opening and delegating of the file to for both opening the file and delegating it to
the client. This document extends NFSv4.2 (see RFC7863). the client. This document extends NFSv4.2 (see RFC 7863).
</t> </t>
</abstract> </abstract>
<note removeInRFC="true">
<t>
Discussion of this draft takes place
on the NFSv4 working group mailing list (nfsv4@ietf.org),
which is archived at
<eref target="https://mailarchive.ietf.org/arch/browse/nfsv4/"/>.
Working Group information can be found at
<eref target="https://datatracker.ietf.org/wg/nfsv4/about/"/>.
</t>
</note>
</front> </front>
<middle> <middle>
<section anchor="sec_intro" numbered="true" removeInRFC="false" toc="default"> <section anchor="sec_intro" numbered="true" toc="default">
<name>Introduction</name> <name>Introduction</name>
<t> <t>
In the Network File System version4 (NFSv4), a client may be granted In the Network File System version 4 (NFSv4), a client may be granted a
a delegation for a file (see Section 1.8.4 of <xref target="RFC8881" delegation for a file (see <xref target="RFC8881" section="1.8.4"
format="default" sectionFormat="of"/>). This allows the client to act as the sectionFormat="of"/>). This allows the client to act as the authority for
authority for the file's metadata and data. This document presents the file's data and metadata. This document presents a number of
a number of extensions which enhance the functionality of opens and extensions that enhance the functionality of opens and delegations. These
delegations. These allow the client to: allow the client to:
</t> </t>
<ul spacing="normal"> <ul spacing="normal">
<li> <li>detect an offline file, which may require significant effort to obtain;<
detect an offline file, which may require significant effort to obtain. /li>
</li>
<li> <li>determine which extensions of OPEN flags are supported by the server;</l
determine which extensions of OPEN (see Section 18.16 of <xref i>
target="RFC8881" format="default" sectionFormat="of"/>) flags are
supported by the server. <li>retrieve either the open or delegation stateid, but not
</li> both simultaneously, during the OPEN procedure; and</li>
<li>
during the OPEN procedure, retrieve either the open stateid <li>cache both the access and modify timestamps, thereby reducing the
(see Section 8.2 of <xref target="RFC8881" frequency with which the client must query the server for this
format="default" sectionFormat="of"/>) or information.
delegation stateid, but not both simultaneously.
</li>
<li>
cache both the access and modify timestamps, thereby reducing
the frequency with which the client must query the server for
this information.
</li> </li>
</ul> </ul>
<t> <t>
Using the process detailed in <xref target="RFC8178" format="default" Using the process detailed in <xref target="RFC8178" format="default"
sectionFormat="of"/>, the revisions in this document become an sectionFormat="of"/>, the revisions in this document become an extension
extension of NFSv4.2 <xref target="RFC7862" format="default" of NFSv4.2 <xref target="RFC7862" format="default"
sectionFormat="of"/>. They are built on top of the external data sectionFormat="of"/>. They are built on top of the External Data
representation (XDR) <xref target="RFC4506" format="default" Representation (XDR) <xref target="RFC4506" format="default"
sectionFormat="of"/> generated from <xref target="RFC7863" sectionFormat="of"/> generated from <xref target="RFC7863"
format="default" sectionFormat="of"/>. format="default" sectionFormat="of"/>.
</t> </t>
<section anchor="sec_defs" numbered="true" removeInRFC="false" toc="default"> <section anchor="sec_defs" numbered="true" toc="default">
<name>Definitions</name> <name>Definitions</name>
<t>This document uses the following terminology:</t>
<dl newline="false" spacing="normal"> <dl newline="false" spacing="normal">
<dt>offline file:</dt> <dt>offline file:</dt>
<dd> <dd>
A file which exists on a device which is not connected to the A file that exists on a device that is not connected to the
server. There is typically a cost associated with bringing the server. There is typically a cost associated with bringing the
file to an online status. Historically this would be a file on file to an online status. Historically, this would be a file on
tape media and the cost would have been finding and loading the tape media, and the cost would have been finding and loading the
tape. A more modern interpretation is that the file is in the tape. A more modern interpretation is that the file is in the
cloud and the cost is a monetary one in downloading the file. cloud, and the cost is a monetary one in downloading the file.
</dd> </dd>
<dt>proxy:</dt> <dt>proxy:</dt>
<dd> <dd>
Proxying of attributes occurs when a client has the authority, as The proxying of attributes occurs when a client has the authority, as
granted by the appropriate delegation, to represent the attributes granted by the appropriate delegation, to represent the attributes
normally maintained by the server. For read attributes, this normally maintained by the server. For read attributes, this
occurs when the client has either a read or write delegations occurs when the client has either a read or write delegation
for the file. For write attributes, this occurs when the client for the file. For write attributes, this occurs when the client
has a write delegation for the file. The client having this has a write delegation for the file. The client having this
authority is the "proxy" for those attributes. authority is the "proxy" for those attributes.
</dd> </dd>
</dl> </dl>
<t>Further, the definitions of the following terms are referenced
as follows:</t>
<ul>
<li>CB_GETATTR (<xref target="RFC8881" section="20.1" sectionFormat="of"/
>)</li>
<li>change (<xref target="RFC8881" section="5.8.1.4" sectionFormat="of"/>
)</li>
<li>CLOSE (<xref target="RFC8881" section="18.2" sectionFormat="of"/>)</l
i>
<li>compound (<xref target="RFC8881" section="2.3" sectionFormat="of"/>)<
/li>
<li>DELEGRETURN (<xref target="RFC8881" section="18.6" sectionFormat="of"
/>)</li>
<li>GETATTR (<xref target="RFC8881" section="18.7" sectionFormat="of"/>)<
/li>
<li>LAYOUTGET (<xref target="RFC8881" section="18.43" sectionFormat="of"/
>)</li>
<li>LOCK (<xref target="RFC8881" section="18.10" sectionFormat="of"/>)</l
i>
<li>NFS4ERR_DELAY (<xref target="RFC8881" section="15.1.1.3" sectionForma
t="of"/>)</li>
<li>OPEN (<xref target="RFC8881" section="18.16" sectionFormat="of"/>)</l
i>
<li>open_delegation_type4 (<xref target="RFC8881" section="18.16.1" secti
onFormat="of"/>)</li>
<li>READ (<xref target="RFC8881" section="18.22" sectionFormat="of"/>)</l
i>
<li>READDIR (<xref target="RFC8881" section="18.23" sectionFormat="of"/>)
</li>
<li>SETATTR (<xref target="RFC8881" section="18.30" sectionFormat="of"/>)
</li>
<li>stateid (<xref target="RFC8881" section="8.2" sectionFormat="of"/>)</
li>
<li>time_access (<xref target="RFC8881" section="5.8.2.37" sectionFormat=
"of"/>)</li>
<li>time_metadata (<xref target="RFC8881" section="5.8.2.42" sectionForma
t="of"/>)</li>
<li>time_modify (<xref target="RFC8881" section="5.8.2.43" sectionFormat=
"of"/>)</li>
<li>WRITE (<xref target="RFC8881" section="18.32" sectionFormat="of"/>)</
li>
</ul>
</section> </section>
<section numbered="true" removeInRFC="false" toc="default"> <section numbered="true" toc="default">
<name>Requirements Language</name> <name>Requirements Language</name>
<t> <t>
The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>",
"<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>
NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", ",
"<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>",
"<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
document are to be interpreted as described in BCP&nbsp;14 <xref "<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document are to
target="RFC2119" format="default" sectionFormat="of"/> <xref be
target="RFC8174" format="default" sectionFormat="of"/> when, interpreted as described in BCP&nbsp;14 <xref target="RFC2119"/> <xref
and only when, they appear in all capitals, as shown here. target="RFC8174"/> when, and only when, they appear in all capitals, as
</t> shown here.
</t>
</section> </section>
</section> </section>
<section anchor="sec_offline" numbered="true" removeInRFC="false" toc="default"> <section anchor="sec_offline" numbered="true" toc="default">
<name>Offline Files</name> <name>Offline Files</name>
<t> <t>
If a file is offline, then the server has immediate high-performance If a file is offline, then the server has immediate high-performance
access to the file's attributes, but not to the file's content. access to the file's attributes, but not to the file's content.
The action of retrieving the data content is expensive, to the extent The action of retrieving the data content is expensive, to the extent
that the content should only be retrieved if it is going to be used. that the content should only be retrieved if it is going to be used.
For example, a graphical file manager (such as OSX's Finder) may For example, a graphical file manager (such as Finder in Mac OS X) may
want to access the beginning of the file to preview it for an user want to access the beginning of the file to preview it for a user
who is hovering their pointer over the file name and not accessing who is hovering their pointer over the file name and not accessing
it otherwise. If the file is retrieved, it will most likely either it otherwise. If the file is retrieved, it will most likely be either
be immediately thrown away or returned. immediately thrown away or returned.
</t> </t>
<t> <t>
A compound (see Section 2.3 of <xref target="RFC8881" format="default" A compound with a GETATTR or READDIR can report the file's attributes
sectionFormat="of"/>) with a GETATTR (see Section 18.7 of <xref without bringing the file online. However, either an OPEN or a LAYOUTGET
target="RFC8881" format="default" sectionFormat="of"/>) or READDIR might cause the file server to retrieve the archived data contents, bringing
(see Section 18.23 of <xref target="RFC8881" format="default" the
sectionFormat="of"/>) can report the file's attributes without file online. For non-parallel NFS systems (see <xref
bringing the file online. However, either an OPEN or a LAYOUTGET target="RFC8881" section="12" sectionFormat="of"/>), the OPEN operation
(see Section 18.43 of <xref target="RFC8881" format="default" requires a filehandle to retrieve the data content. For parallel NFS (pNFS)
sectionFormat="of"/>) might cause the file server to retrieve the systems, the
archived data contents, bringing the file online. For non-parallel filehandle retrieved from an OPEN need not cause the data content to be
NFS (pNFS) systems (see Section 12 of <xref target="RFC8881" retrieved. However, when the LAYOUTGET operation is processed, a layout-type
format="default" sectionFormat="of"/>) , the OPEN operation -specific mapping
requires a filehandle to the data content. For pNFS systems, the will cause the data content to be retrieved from offline
filehandle retrieved from an OPEN need not cause the data content storage.
to be retrieved. But when the LAYOUTGET operation is processed,
a layout type specific mapping will cause the data content to be
retrieved from offline storage.
</t> </t>
<t> <t>
If the client is not aware that the file is offline, it might If the client is not aware that the file is offline, it might
inadvertently open the file to determine what type of file it inadvertently open the file to determine what type of file it
is accessing. By interrogating the new attribute fattr4_offline, is accessing. By interrogating the new attribute fattr4_offline,
a client can predetermine the availability of the file, avoiding the a client can predetermine the availability of the file, avoiding the
need to open it at all. Being offline might also involve situations need to open it at all. Being offline might also involve situations
in which the file is archived in the cloud, i.e., there can be an in which the file is archived in the cloud, i.e., there can be an
expense in both retrieving the file to bring online and in sending expense in both retrieving the file to bring it online and in sending
the file back to offline status. the file back to offline status.
</t> </t>
<section anchor="ssec_offline_attr" numbered="true" removeInRFC="false" toc="d <section anchor="ssec_offline_attr" numbered="true" toc="default">
efault"> <name>XDR for the Offline Attribute</name>
<name>XDR for Offline Attribute</name>
<sourcecode name="" type="" markers="true"><![CDATA[ <sourcecode name="" type="xdr" markers="true"><![CDATA[
/// ///
/// typedef bool fattr4_offline; /// typedef bool fattr4_offline;
/// ///
/// ///
/// const FATTR4_OFFLINE = 83; /// const FATTR4_OFFLINE = 83;
/// ///
]]> ]]></sourcecode>
</sourcecode>
</section> </section>
</section> </section>
<section anchor="ssec_open_xor_xdr" numbered="true" removeInRFC="false" toc="def ault"> <section anchor="ssec_open_xor_xdr" numbered="true" toc="default">
<name>Determining OPEN Feature Support</name> <name>Determining OPEN Feature Support</name>
<t> <t>
<xref target="RFC8178" format="default" sectionFormat="of"/> <xref target="RFC8178" section="4.4.2" sectionFormat="of"/> allows for
(see Section 4.4.2) allows for extending a particular minor extending a particular minor version of the NFSv4 protocol without
version of the NFSv4 protocol without requiring the definition requiring the definition of a new minor version. The client can probe the
of a new minor version. The client can probe the capabilities of capabilities of the server and, based on the result, determine if both it
the server and based on the result, determine if both it and the and the server support optional features not previously specified as part
server support optional features not previously specified as part
of the minor version. of the minor version.
</t> </t>
<t> <t>
The fattr4_open_arguments attribute is a new XDR extension which The fattr4_open_arguments attribute is a new XDR extension that
provides helpful support when the OPEN procedure is extended in provides helpful support when the OPEN procedure is extended in
such a fashion. It models all of the parameters via bitmap4 data such a fashion. It models all of the parameters via bitmap4 data
structures, which allows for the addition of a new flag to any of structures, which allows for the addition of a new flag to any of
the OPEN arguments (see Section 18.16.1 of <xref target="RFC8881" the OPEN arguments. The scope of this attribute
format="default" sectionFormat="of"/>). The scope of this attribute
applies to all objects with a matching fsid. applies to all objects with a matching fsid.
</t> </t>
<t> <t>
Two new flags are provided: Two new flags are provided:
</t> </t>
<ul spacing="normal"> <ul spacing="normal">
<li> <li>
OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION
(see <xref target="sec_open_xor" format="default" sectionFormat="of"/>) (see <xref target="sec_open_xor" format="default" sectionFormat="of"/>)
</li> </li>
<li> <li>
OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS
(see <xref target="sec_proxy" format="default" sectionFormat="of"/>) (see <xref target="sec_proxy" format="default" sectionFormat="of"/>)
</li> </li>
</ul> </ul>
<t> <t>
Subsequent extensions can use this framework when introducing new Subsequent extensions can use this framework when introducing new
<bcp14>OPTIONAL</bcp14> functionality to OPEN, by creating a new <bcp14>OPTIONAL</bcp14> functionality to OPEN by creating a new
flag for each <bcp14>OPTIONAL</bcp14> parameter. flag for each <bcp14>OPTIONAL</bcp14> parameter.
</t> </t>
<t> <t>
Since fattr4_open_arguments is a <bcp14>RECOMMENDED</bcp14> attribute, if th e Since fattr4_open_arguments is a <bcp14>RECOMMENDED</bcp14> attribute, if th e
server informs the client via NFS4ERR_ATTRNOTSUPP that it does not support t his new server informs the client via NFS4ERR_ATTRNOTSUPP that it does not support t his new
attribute, the client <bcp14>MUST</bcp14> take this to mean that attribute, the client <bcp14>MUST</bcp14> take this to mean that
the additional new <bcp14>OPTIONAL</bcp14> functionality to OPEN the additional new <bcp14>OPTIONAL</bcp14> functionality to OPEN
is also not supported. is also not supported.
</t> </t>
<t> <t>
Some other concerns are how to process both currently Some other concerns are how to process both currently
<bcp14>REQUIRED</bcp14> flags and <bcp14>OPTIONAL</bcp14> flags <bcp14>REQUIRED</bcp14> flags and <bcp14>OPTIONAL</bcp14> flags that
which become <bcp14>REQUIRED</bcp14> in the future. The server become <bcp14>REQUIRED</bcp14> in the future. The server
<bcp14>MUST</bcp14> mark <bcp14>REQUIRED</bcp14> flags as being supported. <bcp14>MUST</bcp14> mark <bcp14>REQUIRED</bcp14> flags as being supported.
Note that these flags <bcp14>MUST</bcp14> only change from Note that these flags <bcp14>MUST</bcp14> only change from
<bcp14>OPTIONAL</bcp14> to <bcp14>REQUIRED</bcp14> when the NFSv4 <bcp14>OPTIONAL</bcp14> to <bcp14>REQUIRED</bcp14> when the NFSv4 minor
minor version is incremented. version is incremented.
</t> </t>
<section anchor="ssec_open_xdr" numbered="true" removeInRFC="false" toc="defau lt"> <section anchor="ssec_open_xdr" numbered="true" toc="default">
<name>XDR for Open Arguments</name> <name>XDR for Open Arguments</name>
<sourcecode name="" type="" markers="true"><![CDATA[
<sourcecode name="" type="xdr" markers="true"><![CDATA[
/// ///
/// struct open_arguments4 { /// struct open_arguments4 {
/// bitmap4 oa_share_access; /// bitmap4 oa_share_access;
/// bitmap4 oa_share_deny; /// bitmap4 oa_share_deny;
/// bitmap4 oa_share_access_want; /// bitmap4 oa_share_access_want;
/// bitmap4 oa_open_claim; /// bitmap4 oa_open_claim;
/// bitmap4 oa_create_mode; /// bitmap4 oa_create_mode;
/// }; /// };
/// ///
/// ///
skipping to change at line 332 skipping to change at line 345
/// % * Determine what OPEN supports. /// % * Determine what OPEN supports.
/// % */ /// % */
/// const FATTR4_OPEN_ARGUMENTS = 86; /// const FATTR4_OPEN_ARGUMENTS = 86;
/// ///
/// ///
/// const OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION = 0x200000; /// const OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION = 0x200000;
/// ///
/// ///
/// const OPEN4_RESULT_NO_OPEN_STATEID = 0x00000010; /// const OPEN4_RESULT_NO_OPEN_STATEID = 0x00000010;
/// ///
]]> ]]></sourcecode>
</sourcecode>
</section> </section>
</section> </section>
<section anchor="sec_open_xor" numbered="true" removeInRFC="false" toc="default" <section anchor="sec_open_xor" numbered="true" toc="default">
> <name>OPEN Grants Either an Open or a Delegation Stateid</name>
<name>OPEN grants only one of Open or Delegation Stateid</name>
<t> <t>
The OPEN (See Section 18.16 of <xref target="RFC8881" format="default" The OPEN
sectionFormat="of"/>) procedure returns an open stateid to the procedure returns an open stateid to the client to reference the state of
client to reference the state of the file. The client could also the file. The client could also request a delegation stateid in the OPEN
request a delegation stateid in the OPEN arguments. The file can arguments. The file can be considered open for the client as long as the
be considered open for the client as long as the count of open count of open and delegated stateids is greater than 0. Either type of
and delegated stateids is greater than 0. Either type of stateid stateid is sufficient to enable the server to treat the file as if it were
is sufficient to enable the server to treat the file as if it were open, which allows READ, WRITE, LOCK, and LAYOUTGET operations to proceed.
open, which allows READ (See Section 18.25 of <xref target="RFC8881" If the client
format="default" sectionFormat="of"/>), WRITE (See Section 18.38 gets both an open and a delegation stateid as part of the OPEN, then it
of <xref target="RFC8881" format="default" sectionFormat="of"/>), has to return them both to the server. A further consideration is that
LOCK (See Section 18.12 of <xref target="RFC8881" format="default" during each operation, the client can send a costly GETATTR.
sectionFormat="of"/>), and LAYOUTGET (see Section 18.50 of <xref
target="RFC8881" format="default" sectionFormat="of"/>) operations
to proceed. If the client gets both an open and a delegation stateid
as part of the OPEN, then it has to return them both to the server. A furth
er
consideration is that during each operation, the client can send
a costly GETATTR (See Section 18.7 of <xref target="RFC8881"
format="default" sectionFormat="of"/>).
</t> </t>
<t> <t>
If the client knows that the server supports the If the client knows that the server supports the
OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag (as determined by an OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag (as determined by an
earlier GETATTR operation which queried for the fattr4_open_arguments earlier GETATTR operation that queried for the fattr4_open_arguments
attribute), then the client can supply that flag during the OPEN attribute), then the client can supply that flag during the OPEN and
and only get either an open or delegation stateid. get either an open or a delegation stateid.
</t> </t>
<t> <t>
The client is already prepared to not get a delegation The client is already prepared to not get a delegation
stateid even if requested. In order to not send an open stateid, even if requested. In order to not send an open
stateid, the server <bcp14>MUST</bcp14> indicate that fact with the result stateid, the server <bcp14>MUST</bcp14> indicate that fact with the result
flag of OPEN4_RESULT_NO_OPEN_STATEID. The open stateid field, flag of OPEN4_RESULT_NO_OPEN_STATEID. The open stateid field,
OPEN4resok.stateid (see Section 18.16.2 of <xref target="RFC8881" OPEN4resok.stateid, <bcp14>MUST</bcp14> be set to the
format="default" sectionFormat="of"/>), <bcp14>MUST</bcp14> be set to the special all-zero stateid in this case.
special all zero stateid in this case.
</t> </t>
<t>
Note that the OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag <t>
is a hint. The server might return both stateids. Consider Note that the OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag is a
the scenario in which the client opens a file read-only (with hint. The server might return both stateids. Consider the scenario in
OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION set) and gets only which the client opens a file for read-only (with
an open stateid. If the client then opens the file for read-write OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION set) and only gets an open
(with OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION set), then stateid. If the client then opens the file for read-write (with
the server has three options: OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION set), the server can return
one of the following three options:
</t> </t>
<ol> <ol>
<li>Only an open stateid with the correct seqid.</li> <li>Only an open stateid with the correct seqid.</li>
<li>Only a delegation stateid with the open stateid now having an incorrect seqid as it needs to be upgraded.</li> <li>Only a delegation stateid with the open stateid now having an incorrect seqid as it needs to be upgraded.</li>
<li>Both an open (which will be upgraded) and a delegation stateid.</li> <li>Both an open stateid (which will be upgraded) and a delegation stateid.< /li>
</ol> </ol>
<t> <t>
In this scenario, returning just a delegation stateid would hide information In this scenario, returning just a delegation stateid would hide
from the client. If the client already has an open stateid, then the information from the client. If the client already has an open stateid,
server <bcp14>SHOULD</bcp14> ignore the OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DEL then the server <bcp14>SHOULD</bcp14> ignore the
EGATION OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag and return both the open
flag and return both the open and delegation stateids. and delegation stateids.
</t> </t>
<section anchor="delstid_analysis" numbered="true" removeInRFC="false" toc="de
fault"> <section anchor="delstid_analysis" numbered="true" toc="default">
<name>Implementation Experience</name> <name>Implementation Experience</name>
<t> <t>
The CLOSE operation (see Section The CLOSE operation neither explicitly nor implicitly releases any
18.2 of <xref target="RFC8881" format="default" sectionFormat="of"/>)
neither explicitly nor implicitly releases any
delegation stateids. This is not symmetrical with the OPEN operation, delegation stateids. This is not symmetrical with the OPEN operation,
which can grant both an open and a delegation stateid. This specification which can grant both an open and a delegation stateid. This specification
could have tried to extend the CLOSE operation to release both could have tried to extend the CLOSE operation to release both
stateids, but implementation experience shows that is more costly stateids, but implementation experience shows that is more costly
than the approach which has been proposed. than the approach that has been proposed.
</t> </t>
<t> <t>
Consider a small workload of creating a file with content. That Consider a small workload of creating a file with content. This involves
takes 3 synchronous and 1 asynchronous operations with existing three synchronous operations and one asynchronous operation with
implementations. The first synchronous one has to OPEN the file, existing implementations:</t>
the second synchronous one performs the WRITE to the file, the third
synchronous one has to CLOSE the file, and the fourth asynchronous <ul spacing="normal">
one uses DELEGRETURN (see Section <li>The first synchronous operation has to OPEN the file.</li>
18.6 of <xref target="RFC8881" format="default" sectionFormat="of"/>) <li>The second synchronous operation performs the WRITE to the file.</li>
to return the delegation stateid. <li>The third synchronous operation has to CLOSE the file.</li>
</t> <li>The asynchronous operation uses DELEGRETURN to return the delegation s
<sourcecode name="" type="" markers="true"><![CDATA[ tateid.</li>
</ul>
<sourcecode name="" type="pseudocode" markers="true"><![CDATA[
SEQ PUTFH OPEN GETFH GETATTR SEQ PUTFH OPEN GETFH GETATTR
SEQ PUTFH WRITE GETATTR SEQ PUTFH WRITE GETATTR
SEQ PUTFH CLOSE SEQ PUTFH CLOSE
... ...
SEQ PUTFH DELEGRETURN SEQ PUTFH DELEGRETURN
]]> ]]></sourcecode>
</sourcecode>
<t> <t>
With the proposed approach of setting the With the proposed approach of setting the
OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag during OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag during
the OPEN, the number of operations is always 3. The first two the OPEN, the number of operations is always three. The first two
compounds are still synchronous, but the last is asynchronous. I.e., compounds are still synchronous, but the last is asynchronous. That is,
since the client no longer has to send a CLOSE operation, it can since the client no longer has to send a CLOSE operation, it can
delay the DELEGRETURN until either the server requests it back delay the DELEGRETURN until either the server requests it back
via delegation recall or garbage collection causes the client to via delegation recall or garbage collection causes the client to
return the stateid. return the stateid.
</t> </t>
<sourcecode name="" type="" markers="true"><![CDATA[ <sourcecode name="" type="pseudocode" markers="true"><![CDATA[
SEQ PUTFH OPEN(OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION) SEQ PUTFH OPEN(OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION)
GETFH GETATTR GETFH GETATTR
SEQ PUTFH WRITE GETATTR SEQ PUTFH WRITE GETATTR
... ...
SEQ PUTFH DELEGRETURN SEQ PUTFH DELEGRETURN
]]> ]]></sourcecode>
</sourcecode>
<t> <t>
This approach reduces the cost of synchronous operations by 33% This approach reduces the cost of synchronous operations by 33%
and the total number of operations by 25%. Contrast that against and the total number of operations by 25%. Contrast that with
the alternative proposal of having CLOSE return both stateids, the alternative proposal of having CLOSE return both stateids,
which would not reduce the number of synchronous operations. which would not reduce the number of synchronous operations.
</t> </t>
</section> </section>
</section> </section>
<section anchor="sec_proxy" numbered="true" removeInRFC="false" toc="default"> <section anchor="sec_proxy" numbered="true" toc="default">
<name>Proxying of Times</name> <name>Proxying of Times</name>
<t>
<t>
When a client is granted a write delegation on a file, it becomes the When a client is granted a write delegation on a file, it becomes the
authority for the file contents and associated attributes. If the authority for the file contents and associated attributes. If the server
server queries the client as to the state of the file via a CB_GETATTR queries the client as to the state of the file via a CB_GETATTR, then accord
(see Section 20.1 of <xref target="RFC8881" format="default" ing to
sectionFormat="of"/>), then, according to the unextended NFSv4 the unextended NFSv4 protocol, it can only determine the size of the file
protocol, it can only determine the size of the file and the change and the change attribute. In the case of the client holding the
attribute. In the case of the client holding the delegation, it has delegation, it has the current values of the access and modify times.
the current values of the access and modify times. There is no way There is no way that other clients can have access to these values. To
that other clients can have access to these values. While the notify the server of the proxied values, the client could send a compound
client could send a compound of the form: SEQ, PUTFH, of the form SEQ, PUTFH, SETATTR (time_modify | time_access), DELEGRETURN;
SETATTR (time_modify | time_access), DELEGRETURN, to notify however, the SETATTR operation would cause either or both of the change attr
the server of the proxied values, that SETATTR (see Section 18.30 of <xref t ibute
arget="RFC8881" format="default" or time_metadata attribute to be modified to the current time on the server.
sectionFormat="of"/>) operation would
cause either or both of change (see Section 5.8.1.4 of <xref target="RFC8881 There is no current provision to obtain these values before
" format="default" delegation return using CB_GETATTR. As a result, it cannot pass on these
sectionFormat="of"/>) or time_metadata (see Section 5.8.2.42 of <xref target times to an application expecting POSIX compliance, as is often
="RFC8881" format="default" necessary for correct operation.
sectionFormat="of"/>) to
be modified to the current time on the server.
There is no current provision to obtain these values before delegation
return using CB_GETATTR. As a result, it can not pass these times up
to an application expecting POSIX compliance, as is often necessary
for correct operation.
</t> </t>
<t> <t>
With the addition of the new flag: With the addition of the new
OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS, the client and server can OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS flag, the client and server can
negotiate that the client will be the authority for these values and negotiate that the client will be the authority for these values, and upon
upon return of the delegation stateid via a DELEGRETURN (see section return of the delegation stateid via a DELEGRETURN, the times will be
18.6 of <xref target="RFC8881" format="default" sectionFormat="of"/>), passed back to the server. If the server is queried by another client for
the times will be passed back to the server. If the server is queried either the size or the times, it will need to use a CB_GETATTR to query
by another client for either the size or the times, it will need to the client that holds the delegation.
use a CB_GETATTR to query the client which holds the delegation
(see Section 20.1 of <xref target="RFC8881" format="default"
sectionFormat="of"/>).
</t> </t>
<t> <t>
If a server informs the client via the fattr4_open_arguments attribute If a server informs the client via the fattr4_open_arguments attribute
that it supports OPEN_ARGS_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS and that it supports OPEN_ARGS_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS and it
it returns a valid delegation stateid for an OPEN operation which returns a valid delegation stateid for an OPEN operation that sets the
sets the OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS flag, then it OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS flag, then it <bcp14>MUST</bcp14>
<bcp14>MUST</bcp14> query the client via a CB_GETATTR for the query the client via a CB_GETATTR for the fattr4_time_deleg_access
fattr4_time_deleg_access (see <xref target="ssec_proxy_xdr"/>) attribute (see <xref target="ssec_proxy_xdr"/>) and the
attribute and fattr4_time_deleg_modify attribute (see <xref fattr4_time_deleg_modify attribute (see <xref
target="ssec_proxy_xdr"/>). (The change time can be derived from target="ssec_proxy_xdr"/>). (Note that the change time can be derived from
the modify time.) Further, when it gets a SETATTR with those the modify time.) Further, when a server gets a SETATTR with those attribute
attributes being set, then it <bcp14>MUST</bcp14> accept those s
fattr4_time_deleg_access attribute and fattr4_time_deleg_modify set, then it <bcp14>MUST</bcp14> accept those changes in the
attribute changes and derive the change time or reject the changes fattr4_time_deleg_access and fattr4_time_deleg_modify
with NFS4ERR_DELAY (see Section 15.1.1.3 of <xref target="RFC8881" attributes and derive the change time, or it <bcp14>MUST</bcp14> reject the
format="default" sectionFormat="of"/>). changes with
NFS4ERR_DELAY.
</t> </t>
<t> <t>
These new attributes are invalid to be used with GETATTR, VERIFY, and NVERIF When the server grants a delegation stateid, it
Y and <bcp14>MUST</bcp14> inform the client by setting the appropriate
flag in the open_delegation_type4 response.
The server <bcp14>MUST</bcp14> set OPEN_DELEGATE_READ_ATTRS_DELEG when it
grants a read attribute delegation and <bcp14>MUST</bcp14> set
OPEN_DELEGATE_WRITE_ATTRS_DELEG when it grants a write attribute
delegation.
</t>
<t>
These new attributes are invalid to be used with GETATTR, VERIFY, and NVERIF
Y, and they
can only be used with CB_GETATTR and SETATTR by a client holding an can only be used with CB_GETATTR and SETATTR by a client holding an
appropriate delegation. The SETATTR <bcp14>SHOULD</bcp14> either be appropriate delegation. The SETATTR <bcp14>SHOULD</bcp14> be either
in a separate compound before the one containing the DELEGRETURN or 1) in a separate compound before the one containing the DELEGRETURN or
when in the same compound, as an operation before the DELEGRETURN. 2) in the same compound as an operation before the DELEGRETURN.
Failure to properly sequence the operations may lead to race conditions. Failure to properly sequence the operations may lead to race conditions.
</t> </t>
<t> <t>
A key prerequisite of this approach is that the server and client are A key prerequisite of this approach is that the server and client are in
in time synchronization with each other. Note that while the base time synchronization with each other. Note that while the base NFSv4.2
NFSv4.2 does not require such synchronization, the use of RPCSEC_GSS does not require such synchronization, the use of RPCSEC_GSS typically
typically makes such a requirement. When the client presents either makes such a requirement. When the client presents either the
fattr4_time_deleg_access or fattr4_time_deleg_modify attributes fattr4_time_deleg_access or the fattr4_time_deleg_modify attribute to the
to the server, the server <bcp14>MUST</bcp14> decide for both of server, the server <bcp14>MUST</bcp14> decide for both of them whether the t
them whether the time presented is before the corresponding ime presented is:</t>
time_access (see Section 5.8.2.37 of <xref target="RFC8881" format="default"
sectionFormat="of"/>) or time_modify (see Section 5.8.2.43 of <xref target=" <ul>
RFC8881" format="default" <li>before the corresponding time_access attribute or time_modify
sectionFormat="of"/>) attribute attribute on the file, or</li>
on the file or past the current server time. <li>past the current server time.</li>
When the time presented is before the original time, then the update </ul>
is ignored. When the time presented is in the future, the server
can either clamp the new time to the current time, or it may return <t>When the time
NFS4ERR_DELAY to the client, allowing it to retry. Note that if the presented is before the original time, then the update is ignored. When
clock skew is large, the delay approach would result in access to the time presented is in the future, the server can either clamp the new
the file being denied until the clock skew is exceeded. time to the current time or return NFS4ERR_DELAY to the client,
allowing it to retry. Note that if the clock skew is large, the delay
approach would result in access to the file being denied until the clock
skew is exceeded.
</t> </t>
<t> <t>
A change in the access time <bcp14>MUST NOT</bcp14> advance the change time, A change in the access time <bcp14>MUST NOT</bcp14> advance the change
also known as the time_metadata attribute (see Section 5.8.2.42 of time, also known as the time_metadata attribute. However, a
<xref target="RFC8881" format="default" sectionFormat="of"/>), but a change in the modify time might advance the change time (and in turn, the
change in the modify time might advance the change time (and in turn change attribute). If the modify time is greater than the change time
the change attribute (See Section 5.8.1.4 of <xref target="RFC8881" and before the current time, then the change time is adjusted to the
format="default" sectionFormat="of"/>). If the modify time is greater modify time and not the current time (as is most likely done on most
than the change time and before the current time, then the change time SETATTR calls that change the metadata). If the modify time is in the
is adjusted to the modify time and not the current time (as is most future, it will be clamped to the current time.
likely done on most SETATTR calls that change the metadata). If the
modify time is in the future, it will be clamped to the current time.
</t> </t>
<t> <t>
Note that each of the possible times, access, modify, and change, are Note that each of the possible times (access, modify, and change) are
compared to the current time. They should all be compared against compared to the current time. They should all be compared against
the same time value for the current time. I.e., do not retrieve the same time value for the current time (i.e., they do not retrieve
a different value of the current time for each calculation. a different value of the current time for each calculation).
</t> </t>
<t> <t>
If the client sets the OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS If the client sets the OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS
flag in an OPEN operation, then it <bcp14>MUST</bcp14> support flag in an OPEN operation, then it <bcp14>MUST</bcp14> support
the fattr4_time_deleg_access the fattr4_time_deleg_access
and fattr4_time_deleg_modify attributes both in the CB_GETATTR and fattr4_time_deleg_modify attributes in both the CB_GETATTR
and SETATTR operations. and SETATTR operations.
</t> </t>
<section anchor="ssec_proxy_use" numbered="true" removeInRFC="false" toc="defa <section anchor="ssec_proxy_use" numbered="true" toc="default">
ult"> <name>Use Case for NFSv3 Client Proxy</name>
<name>Use case: NFSv3 client proxy</name>
<t> <t>
Consider a NFSv3 client which wants to access data on a server Consider an NFSv3 client that wants to access data on a server
which only supports NFSv4.2. An implementation may introduce an that only supports NFSv4.2. An implementation may introduce an
NFSv3 server that functions as an NFSv4.2 client, serving as a NFSv3 server that functions as an NFSv4.2 client, serving as a
gateway between the two otherwise incompatible systems. As NFSv3 gateway between the two otherwise incompatible systems. As NFSv3
is a stateless protocol, the state is not kept on the client, but is a stateless protocol, the state is not kept on the client, but rather
rather the NFSv3 server. As the NFSv3 server is already managing the on the NFSv3 server. As the NFSv3 server is already managing the
state, it can proxy file delegations to avoid spurious GETATTRs. state, it can proxy file delegations to avoid spurious GETATTRs. That is,
I.e., as the client queries the NFSv3 server for the attributes, as the client queries the NFSv3 server for the attributes,
they can be served without the NFSv3 server sending a GETATTR to they can be served without the NFSv3 server sending a GETATTR to
the NFSv4.2 server. the NFSv4.2 server.
</t> </t>
</section> </section>
<section anchor="ssec_proxy_xdr" numbered="true" removeInRFC="false" toc="defa ult"> <section anchor="ssec_proxy_xdr" numbered="true" toc="default">
<name>XDR for Proxying of Times</name> <name>XDR for Proxying of Times</name>
<sourcecode name="" type="" markers="true"><![CDATA[ <sourcecode name="" type="xdr" markers="true"><![CDATA[
/// ///
/// /* /// /*
/// * attributes for the delegation times being /// * attributes for the delegation times being
/// * cached and served by the "client" /// * cached and served by the "client"
/// */ /// */
/// typedef nfstime4 fattr4_time_deleg_access; /// typedef nfstime4 fattr4_time_deleg_access;
/// typedef nfstime4 fattr4_time_deleg_modify; /// typedef nfstime4 fattr4_time_deleg_modify;
/// ///
/// ///
/// %/* /// %/*
/// % * New RECOMMENDED Attribute for /// % * New RECOMMENDED Attribute for
/// % * delegation caching of times /// % * delegation caching of times
/// % */ /// % */
/// const FATTR4_TIME_DELEG_ACCESS = 84; /// const FATTR4_TIME_DELEG_ACCESS = 84;
/// const FATTR4_TIME_DELEG_MODIFY = 85; /// const FATTR4_TIME_DELEG_MODIFY = 85;
/// ///
/// ///
/// const OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS = 0x100000; /// const OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS = 0x100000;
/// ///
]]> /// enum open_delegation_type4 {
</sourcecode> /// OPEN_DELEGATE_NONE = 0,
/// OPEN_DELEGATE_READ = 1,
/// OPEN_DELEGATE_WRITE = 2,
/// OPEN_DELEGATE_NONE_EXT = 3, /* new to v4.1 */
/// OPEN_DELEGATE_READ_ATTRS_DELEG = 4,
/// OPEN_DELEGATE_WRITE_ATTRS_DELEG = 5
/// };
]]></sourcecode>
</section> </section>
</section> </section>
<section anchor="xdr_desc" numbered="true" removeInRFC="false" toc="default"> <section anchor="xdr_desc" numbered="true" toc="default">
<name>Extraction of XDR</name> <name>Extraction of XDR</name>
<t> <t>
This document contains the external data representation (XDR) This document contains the XDR <xref
<xref target="RFC4506" format="default" sectionFormat="of"/> description of target="RFC4506" format="default" sectionFormat="of"/> description of the
the new open new open flags for delegating the file to the client. The XDR description
flags for delegating the file to the client. is embedded in this document in a way that makes it simple for the reader
The XDR description is embedded in this to extract into a ready-to-compile form. The reader can feed this
document in a way that makes it simple for the reader to extract document into the following shell script to produce the machine-readable
into a ready-to-compile form. The reader can feed this document
into the following shell script to produce the machine readable
XDR description of the new flags: XDR description of the new flags:
</t> </t>
<sourcecode name="" type="" markers="true"><![CDATA[
<sourcecode name="" type="shell" markers="true"><![CDATA[
#!/bin/sh #!/bin/sh
grep '^ *///' $* | sed 's?^ */// ??' | sed 's?^ *///$??' grep '^ *///' $* | sed 's?^ */// ??' | sed 's?^ *///$??'
]]> ]]></sourcecode>
</sourcecode>
<t> <t>
That is, if the above script is stored in a file called "extract.sh", and That is, if the above script is stored in a file called "extract.sh" and
this document is in a file called "spec.txt", then the reader can do: this document is in a file called "spec.txt", then the reader can do the
following:
</t> </t>
<sourcecode name="" type="" markers="true"><![CDATA[
<sourcecode name="" type="shell" markers="true"><![CDATA[
sh extract.sh < spec.txt > delstid_prot.x sh extract.sh < spec.txt > delstid_prot.x
]]> ]]></sourcecode>
</sourcecode>
<t> <t>
The effect of the script is to remove leading white space from each The effect of the script is to remove leading blank space from each
line, plus a sentinel sequence of "///". XDR descriptions with the line, plus a sentinel sequence of "///". XDR descriptions with the
sentinel sequence are embedded throughout the document. sentinel sequence are embedded throughout the document.
</t> </t>
<t> <t>
Note that the XDR code contained in this document depends on types Note that the XDR code contained in this document depends on types
from the NFSv4.2 nfs4_prot.x file (generated from from the NFSv4.2 nfs4_prot.x file (generated from <xref target="RFC7863"
<xref target="RFC7863" format="default" sectionFormat="of"/>). format="default" sectionFormat="of"/>). This includes both nfs types that
This includes both nfs types that end with a 4, such as offset4, end with a 4 (such as offset4 and length4) as well as more generic
length4, etc., as well as more generic types such as uint32_t and types (such as uint32_t and uint64_t).
uint64_t.
</t> </t>
<t> <t>
While the XDR can be appended to that from While the XDR can be appended to that from
<xref target="RFC7863" format="default" sectionFormat="of"/>, <xref target="RFC7863" format="default" sectionFormat="of"/>,
the various code snippets belong in their respective areas of the various code snippets belong in their respective areas of
that XDR. that XDR.
</t> </t>
</section> </section>
<section anchor="sec_security" numbered="true" removeInRFC="false" toc="default" > <section anchor="sec_security" numbered="true" toc="default">
<name>Security Considerations</name> <name>Security Considerations</name>
<t> <t>
While we are extending some capabilities for client delegation, there are no While this document extends some capabilities for client delegation, there a
new security concerns. The client cannot be queried by other clients as to re
the cached attributes. The client could report false data for the cached no new security concerns. The client cannot be queried by other clients
attributes, but it already has this ability via a SETATTR operation (see Sec as to the cached attributes. The client could report false data for the
tion cached attributes, but it already has this ability via a SETATTR operation.
18.30 of <xref target="RFC8881" format="default" sectionFormat="of"/>).
</t> </t>
</section> </section>
<section anchor="sec_iana" numbered="true" removeInRFC="false" toc="default"> <section anchor="sec_iana" numbered="true" toc="default">
<name>IANA Considerations</name> <name>IANA Considerations</name>
<t> <t>This document has no IANA actions.</t>
There are no IANA considerations.
</t>
</section> </section>
</middle> </middle>
<back> <back>
<references> <references>
<name>References</name>
<references>
<name>Normative References</name> <name>Normative References</name>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2119 xml"/>
.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.4506.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.4506 <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7862.
.xml"/> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7863.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7862 xml"/>
.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7863 <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8178.
.xml"/> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8881.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8174 xml"/>
.xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8178
.xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8881
.xml"/>
</references>
</references> </references>
<section numbered="true" removeInRFC="false" toc="default"> <section numbered="false" toc="default">
<name>Acknowledgments</name> <name>Acknowledgments</name>
<t> <t><contact fullname="Trond Myklebust"/>, <contact fullname="Tom
Trond Myklebust, Tom Haynes, and David Flynn Haynes"/>, and <contact fullname="David Flynn"/> all worked on the
all worked on the prototype at Hammerspace. prototype at Hammerspace.</t>
</t> <t><contact fullname="Dave Noveck"/>, <contact fullname="Chuck Lever"/>,
<t> <contact fullname="Rick Macklem"/>, and <contact fullname="Zaheduzzaman
Dave Noveck, Chuck Lever, Rick Macklem, and Zaheduzzaman Sarker Sarker"/> provided reviews of the document.</t>
provided reviews of the document. <t><contact fullname="Jeff Layton"/> provided experience from an
</t> implementation he authored.</t>
<t>
Jeff Layton provided experience from an implementation he authored.
</t>
</section> </section>
</back> </back>
</rfc> </rfc>
 End of changes. 102 change blocks. 
367 lines changed or deleted 399 lines changed or added

This html diff was produced by rfcdiff 1.48.