Internet DRAFT - draft-haynes-nfsv4-delstid
draft-haynes-nfsv4-delstid
NFSv4 T. Haynes
Internet-Draft T. Myklebust
Intended status: Standards Track Hammerspace
Expires: January 26, 2020 July 25, 2019
Extending the Opening of Files in NFSv4.2
draft-haynes-nfsv4-delstid-02.txt
Abstract
The Network File System v4 (NFSv4) allows a client to both open a
file and be granted a delegation of that file. This provides the
client the right to cache metadata on the file locally. This
document presents several refinements to both the opening and
delegating of the file to the client.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 26, 2020.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Offline Files . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Determining the Arguments to OPEN . . . . . . . . . . . . . . 4
3.1. XDR Modifications to OPEN . . . . . . . . . . . . . . . . 5
4. Proxying of Times . . . . . . . . . . . . . . . . . . . . . . 7
4.1. Use case . . . . . . . . . . . . . . . . . . . . . . . . 8
4.2. XDR for Proxying of Times . . . . . . . . . . . . . . . . 9
5. Operation 77: LAYOUT_WCC - Layout Weak Cache Consistency . . 9
5.4. Allowed Errors . . . . . . . . . . . . . . . . . . . . . 11
5.5. Flex Files Layout Type . . . . . . . . . . . . . . . . . 11
6. Extraction of XDR . . . . . . . . . . . . . . . . . . . . . . 13
6.1. Code Components Licensing Notice . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
9. Normative References . . . . . . . . . . . . . . . . . . . . 14
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 14
Appendix B. RFC Editor Notes . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
In the Network File System version4 (NFSv4) a client may be granted a
delegation for a file. This allows the client to act as the
authority of the file's metadata and data. In this document, we
introduce some new semantics to both the open and the delegation
process which allows the client to:
o detect an offline file, which may be located off premise.
o determine the extension of OPEN (see Section 18.16 of [RFC5661])
flags.
o during the OPEN procedure, get either the open or delegation
stateids, but not both.
o cache both the access and modify times, reducing the number of
times the client needs to go to the server to get that
information.
o for clients using Parallel NFS (pNFS) (see Section 12 of
[RFC5661]), periodically report the attributes of the data files
to the metadata server.
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Using the process detailed in [RFC8178], the revisions in this
document become an extension of NFSv4.2 [RFC7862]. They are built on
top of the external data representation (XDR) [RFC4506] generated
from [RFC7863].
1.1. Definitions
delegation: A file delegation, which is a recall-able lock that
assures the holder that inconsistent opens and file changes cannot
occur so long as the delegation is held.
stateid: A stateid is a 128-bit quantity returned by a server that
uniquely defines state held by the server for the client. (See
Section 8 of [RFC5661])
weak cache consistency (WCC): In NFSv3, operations are not sent in a
compound, hence the client would have to perform two round trips
to the server in order to determine the result of modification to
the state of a file or directory. With WCC, the server can return
post-operation attributes on such operations. As these do not
provide a strict consistency between the server and client, the
client is free to ignore the data. (See Section 2.6 of [RFC1813])
1.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Offline Files
If a file is offline, then the server locally has the file's
attributes, but not the file's content. It has to be able to present
to the client enough information to describe the file, but the
content is not readily available. The cost of retrieving the data
content is expensive, to the extent that the content should only be
retrieved if it is going to be used. A graphical file manager (such
as OSX's Finder) may want to access the beginning of the file to
preview it for an user who is hovering his pointer over the file
name. If the file is retrieved, it will most likely either be
immediately thrown away or returned.
A compound with a GETATTR or READDIR can report the file's attributes
without bringing the file online. However, either an OPEN or a
LAYOUTGET might cause the file server to retrieve the archived data
contents, bringing the file online. For non-pNFS systems, the OPEN
operation requires a filehandle to the data content. For pNFS
systems, the filehandle retrieved from an OPEN need not cause the
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data content 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.
If an operating system is not aware that the file is offline, it
might inadvertently open the file to determine what type of file it
is accessing. By adding the new attribute FATTR4_OFFLINE, a client
can predetermine the availability of the file, avoiding the need to
open it at all. Being offline might also mean that 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 the file back to
offline status.
<CODE BEGINS>
///
/// typedef bool fattr4_offline;
///
///
/// const FATTR4_OFFLINE = 83;
///
<CODE ENDS>
3. Determining the Arguments to OPEN
The OPEN (See Section 18.16 of [RFC5661]) procedure returns an open
stateid to the client to reference the state of the file. The client
could also request a delegation stateid in the OPEN arguements. The
file is said to be "open" to the client as long as the count of open
and delegated stateids is greater than 0. Either type of stateid is
suffucient to keep the file open, which allows READ (See
Section 18.22 of [RFC5661]), WRITE (See Section 18.2 of [RFC5661]),
LOCK (See Section 18.10 of [RFC5661]), and LAYOUTGET (see
Section 18.43 of [RFC5661]) operations to proceed. If the client
gets both a open and a delegation stateid as part of the OPEN, then
it has to return them both. And during each operation, the client
can send a costly GETATTR (See Section 18.7 of [RFC5661]).
If the client knows that the server supports the
OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION flag (as determined by an
earlier GETATTR operation which queried for the FATTR4_OPEN_ARGUMENTS
attribute), then the client can supply that flag during the OPEN and
only get either an open or delegation stateid.
The client is already prepared to not get a delegation stateid even
if requested. In order to not send an open stateid, the server can
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indicate that fact with the result flag of
OPEN4_RESULT_NO_OPEN_STATEID. The open stateid field,
OPEN4resok.stateid (see Section 18.16.2 of [RFC5661]), should also be
set to the special all zero stateid.
3.1. XDR Modifications to OPEN
[RFC8178] (see Section 4.4.2) allows for extending the microversion
of the NFSv4.x protocol without increasing the microversion. The
client can probe the capabilities of the server and based on that
result, determine if both it and the server support features not
specified in the main microversion docuument.
The XDR extensions presented in this section allow for the OPEN
procedure to be extended in 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 the OPEN arguments (see Section 18.16.1 of
[RFC5661]). Two new flags are provided:
o OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION (see Section 4)
o OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS
Subsequent documents can use this framework to introduce new
functionality to OPEN.
<CODE BEGINS>
///
/// struct open_arguments4 {
/// bitmap4 oa_share_access;
/// bitmap4 oa_share_deny;
/// bitmap4 oa_share_access_want;
/// bitmap4 oa_open_claim;
/// bitmap4 oa_create_mode;
/// };
///
///
/// enum open_args_share_access4 = {
/// OPEN_ARGS_SHARE_ACCESS_READ = 0;
/// OPEN_ARGS_SHARE_ACCESS_WRITE = 1;
/// OPEN_ARGS_SHARE_ACCESS_BOTH = 2;
/// };
///
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///
/// enum open_args_share_deny4 = {
/// OPEN_ARGS_SHARE_DENY_NONE = 0;
/// OPEN_ARGS_SHARE_DENY_READ = 1;
/// OPEN_ARGS_SHARE_DENY_WRITE = 2;
/// };
///
///
/// enum open_args_share_access4 = {
/// OPEN_ARGS_SHARE_ACCESS_WANT_ANY_DELEG = 0;
/// OPEN_ARGS_SHARE_ACCESS_WANT_NO_DELEG = 1;
/// OPEN_ARGS_SHARE_ACCESS_WANT_CANCEL = 2;
/// OPEN_ARGS_SHARE_ACCESS_WANT_SIGNAL_DELEG_WHEN_RESRC_AVAIL
/// = 3;
/// OPEN_ARGS_SHARE_ACCESS_WANT_PUSH_DELEG_WHEN_UNCONTENDED
/// = 4;
/// OPEN_ARGS_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS = 5;
/// OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION = 6;
/// };
///
///
/// enum open_args_share_access4 = {
/// OPEN_ARGS_CLAIM_NULL = 0;
/// OPEN_ARGS_CLAIM_PREVIOUS = 1;
/// OPEN_ARGS_CLAIM_DELEGATE_CUR = 2;
/// OPEN_ARGS_CLAIM_DELEGATE_PREV = 3;
/// OPEN_ARGS_CLAIM_FH = 4;
/// OPEN_ARGS_CLAIM_DELEG_CUR_FH = 5;
/// OPEN_ARGS_CLAIM_DELEG_PREV_FH = 6;
/// };
///
///
/// enum open_args_share_access4 = {
/// OPEN_ARGS_CREATE_MODE_GUARDED = 0;
/// OPEN_ARGS_CREATE_MODE_EXCLUSIVE = 1;
/// };
///
///
/// typedef open_arguments4 fattr4_open_arguments;
///
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///
/// %/*
/// % * Determine what OPEN4 supports.
/// % */
/// const FATTR4_OPEN_ARGUMENTS = 86;
///
///
/// const OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION = 0x200000;
///
///
/// const OPEN4_RESULT_NO_OPEN_STATEID = 0x00000010;
///
<CODE ENDS>
4. Proxying of Times
When a client is granted a write delegation on a file, it is the
authority for the file. If the server queries the client as to the
state of the file via a CB_GETATTR (see Section 20.1 of [RFC5661]),
then it can only determine the size of the file. Likewise, if the
client holding the delegation wants to know either of the access,
modify, or change times, it has to send a GETATTR to the server.
While it is the authority for these values, it has no way to
guarantee these values after the delegation has been returned. And
as such, it can not pass these times up to an application expecting
posix compliance.
With the addition of the new flag:
OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS, the client and server can
negiotiate that the client will be the authority for these values and
upon return of the delegation stateid via a DELEGRETURN (see section
18.6 of [RFC5661]), the times will be passed back to the server. If
the server is queried by another client for either the size or the
times, it will need to use a CB_GETATTR to query the client which
holds the delegation (see Section 20.1 of [RFC5661]).
If a server informs the client via the FATTR4_OPEN_ARGUMENTS
attribute that it supports
OPEN_ARGS_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS and it returns a valid
delegation stateid for an OPEN operation which sets the
OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS flag, then it MUST be able
to query the client via a CB_GETATTR for the FATTR4_TIME_DELEG_ACCESS
attribute and FATTR4_TIME_DELEG_MODIFY attribute. (The change time
can be derived from the modify time.) Further, when it gets a
SETATTR (see Section 18.30 of [RFC5661]) in the same compound as the
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DELEGRETURN, then it MUST accept those FATTR4_TIME_DELEG_ACCESS
attribute and FATTR4_TIME_DELEG_MODIFY attribute changes and derive
the change time or reject the changes with NFS4ERR_DELAY.
A key prerequisite of this approach is that the server and client are
in time synchronization with each other. Note that while the base
NFSv4.2 does not require such synchronization, the use of RPCSEC_GSS
typically makes such a requirement. When the client presents either
FATTR4_TIME_DELEG_ACCESS or FATTR4_TIME_DELEG_MODIFY attributes to
the server, the server MUST decide whether the times presented are
before the old times or past the current time. If the time presented
is before the original time, then the update is ignored. If the time
presented is in the future, the server can either clamp the new time
to the current time, or it may return NFS4ERR_DELAY to the client,
allowing it to retry. Note that if the clock skew is large, this
policy will result in access to the file being denied until such time
that the clock skew is exceeded.
A change in the access time MUST not advance the change time, also
known as the time_metadata attribute (see Section 5.8.2.42 of
[RFC5661]), but a change in the modify time might advance the change
time (and in turn the change attribute (See Section 5.8.1.4 of
[RFC5661]). If the modify time is greater than the change time and
before the current time, then the change time is adjusted to the
modify time and not the current time (as is most 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.
Note that each of the possible times, access, modify, and change, are
compared to the current time. They should all be compared against
the same time value for the current time. I.e., do not retrieve a
different value of the current time for each calculation.
If the client sets the OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS flag
in an OPEN operation, then it MUST support the
FATTR4_TIME_DELEG_ACCESS and FATTR4_TIME_DELEG_MODIFY attributes both
in the CB_GETATTR and SETATTR operations.
4.1. Use case
When a server is a proxy for a NFSv4 server, it is a client to the
NFSv4 server and during file I/O, it may get a delegation on a file.
The client of the proxy would be querying the proxy for attributes
and not the NFSv4 server. Each GETATTR from that client would result
in at least one additional GETATTR being sent across the wire.
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4.2. XDR for Proxying of Times
<CODE BEGINS>
///
/// /*
/// * attributes for the delegation times being
/// * cached and served by the "client"
/// */
/// typedef nfstime4 fattr4_time_deleg_access;
/// typedef nfstime4 fattr4_time_deleg_modify;
///
///
/// %/*
/// % * New RECOMMENDED Attribute for
/// % * delegation caching of times
/// % */
/// const FATTR4_TIME_DELEG_ACCESS = 84;
/// const FATTR4_TIME_DELEG_MODIFY = 85;
///
///
/// const OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS = 0x100000;
///
<CODE ENDS>
5. Operation 77: LAYOUT_WCC - Layout Weak Cache Consistency
5.1. ARGUMENT
<CODE BEGINS>
/// struct LAYOUT_WCC4args {
/// stateid4 lowa_stateid;
/// layouttype4 lowa_type;
/// opaque lowa_body<>;
/// };
<CODE ENDS>
5.2. RESULT
<CODE BEGINS>
/// struct LAYOUT_WCC4res {
/// nfsstat4 lowr_status;
/// };
<CODE ENDS>
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5.3. DESCRIPTION
When using pNFS (See Section 12 of [RFC5661]), the client is most
likely to be performing file operations to the storage device and not
the metadata server. With some layout types (most notably the
flexible files layout type in [RFC8435]) there is no control protocol
between the metadata server and the storage device. In order to
update the metadata state of the file, the metadata server will need
to track the metadata state of the data file - once the layout is
issued, it is not able to see the NFSv3 file operations from the
client to the storage device. Thus the metadata server will be
required to query the storage device for the data file attributes.
For example, with a flexible files layout type, the metadata server
would issue a NFSv3 GETATTR to the storage device. These queries are
most likely triggered in response to a NFSv4 GETATTR to the metadata
server. Not only are these GETATTRs to the storage device
individually expensive, the storage device can become inundated by a
storm of such requests. NFSv3 solved a similar issue by having the
READ and WRITE operations employ a post-operation attribute to report
the weak cache consistency (WCC) data (See Section 2.6 of [RFC1813]).
Each NFSv3 operation corresponds to one round trip between the client
and server. So a WRITE followed by a GETATTR would require two round
trips. In that scenario, the attribute information retrieved is
considered to be strict server-client consistency for a cache
consistency protocol. For NFSv4, the WRITE and GETATTR can be issued
together inside a compound, which only requires one round trip
between the client and server. And this is also considered to be a
strict server-client consistency. In essence, the NFSv4 READ and
WRITE operations drop the post-operation attributes, allowing the
client to decide if it needs that information.
With the flexible files layout type, the client can leverage the
NFSv3 WCC to service the proxying of times (See Section 4). But the
granularity of this data is limited. With client side mirroring (See
Section 8 of [RFC8435]), the client has to aggregate the N mirrored
files in order to send one piece of information instead of N pieces
of information. Also, the client is limited to sending that
information only when it returns the delegation.
The current filehandle and the lowa_stateid identifies the particular
layout for the LAYOUT_WCC operation. The lowa_type indicates how to
unpack the layout type specific payload inside the lowa_body field.
The lowa_type is defined to be a value from the IANA registry for
"pNFS Layout Types Registry".
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The lowa_body will contain the data file attributes. The client will
be responsible for mapping the NFSv3 post-operation attributes to
those in a fattr4. Just as the post-operation attributes may be
ignored by the client, the server may ignore the attributes inside
the LAYOUT_WCC. But the server can also use those attributes to
avoid querying the storage device for the data file attributes. Note
that as these attributes are optional and there is nothing the client
can do if the server ignores one, there is no need to return a
bitmap4 of which attributes were accepted in the result of the
LAYOUT_WCC.
5.4. Allowed Errors
The LAYOUT_WCC operation can raise the errors in Table 1. When an
error is encountered, the metadata server can decide to ignore the
entire operation or depending on the layout type specific payload, it
could decide to apply a portion of the payload.
Valid Error Returns for LAYOUT_WCC
+-------------------------------------------------------------------+
| Errors |
+-------------------------------------------------------------------+
| NFS4ERR_ADMIN_REVOKED, NFS4ERR_BADXDR, NFS4ERR_BAD_STATEID, |
| NFS4ERR_DEADSESSION, NFS4ERR_DELAY, NFS4ERR_DELEG_REVOKED, |
| NFS4ERR_EXPIRED, NFS4ERR_FHEXPIRED, NFS4ERR_GRACE, NFS4ERR_INVAL, |
| NFS4ERR_ISDIR, NFS4ERR_MOVED, NFS4ERR_NOFILEHANDLE, |
| NFS4ERR_NOTSUPP, NFS4ERR_NO_GRACE, NFS4ERR_OLD_STATEID, |
| NFS4ERR_OP_NOT_IN_SESSION, NFS4ERR_REP_TOO_BIG, |
| NFS4ERR_REP_TOO_BIG_TO_CACHE, NFS4ERR_REQ_TOO_BIG, |
| NFS4ERR_RETRY_UNCACHED_REP, NFS4ERR_SERVERFAULT, NFS4ERR_STALE, |
| NFS4ERR_TOO_MANY_OPS, NFS4ERR_UNKNOWN_LAYOUTTYPE, |
| NFS4ERR_WRONG_CRED, NFS4ERR_WRONG_TYPE |
+-------------------------------------------------------------------+
Table 1
5.5. Flex Files Layout Type
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<CODE BEGINS>
/// struct ff_data_server_wcc4 {
/// deviceid4 ffdsw_deviceid;
/// stateid4 ffdsw_stateid;
/// nfs_fh4 ffdsw_fh_vers<>;
/// fattr4 ffdsw_attributes;
/// };
///
/// struct ff_mirror_wcc4 {
/// ff_data_server_wcc4 ffmw_data_servers<>;
/// };
///
/// struct ff_layout_wcc4 {
/// ff_mirror_wcc4 fflw_mirrors<>;
/// };
<CODE ENDS>
The flex file layout type specific results SHOULD correspond to the
ff_layout4 data structure as defined in Section 5.1 of [RFC8435].
There SHOULD be a one-to-one correspondence between:
o ff_data_server4 -> ff_data_server_wcc4
o ff_mirror4 -> ff_mirror_wcc4
o ff_layout4 -> ff_layout_wcc4
Each ff_layout4 has an array of ff_mirror4, which have an array of
ff_data_server4. Based on the current filehandle and the
lowa_stateid, the server can match the reported attributes.
But the positional correspondence between the elements is not
sufficient to determine the attributes to update. Consider the case
where a layout had three mirrors and two of them had updated
attributes, but the third did not. A client could decide to present
all three mirrors, with one mirror having an attribute mask with no
attributes present. Or it could decide to present only the two
mirrors which had been changed.
In either case, the combination of ffdsw_deviceid, ffdsw_stateid, and
ffdsw_fh_vers will uniquely identify the attributes to be updated.
All three arguments are required. A layout might have multiple data
files on the same storage device, in which case the ffdsw_deviceid
and ffdsw_stateid would match, but the ffdsw_fh_vers would not.
The ffdsw_attributes are processed similar to the obj_attributes in
the SETATTR arguments (See Section 18.30 of [RFC5661]).
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6. Extraction of XDR
This document contains the external data representation (XDR)
[RFC4506] description of the new open flags for delegating the file
to the client. The XDR description is embedded in this document in a
way that makes it simple for the reader to extract 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:
<CODE BEGINS>
#!/bin/sh
grep '^ *///' $* | sed 's?^ */// ??' | sed 's?^ *///$??'
<CODE ENDS>
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:
sh extract.sh < spec.txt > delstid_prot.x
The effect of the script is to remove leading white space from each
line, plus a sentinel sequence of "///". XDR descriptions with the
sentinel sequence are embedded throughout the document.
Note that the XDR code contained in this document depends on types
from the NFSv4.2 nfs4_prot.x file (generated from [RFC7863]). This
includes both nfs types that end with a 4, such as offset4, length4,
etc., as well as more generic types such as uint32_t and uint64_t.
While the XDR can be appeneded to that from [RFC7863], the various
code snippets belong in their respective areas of the that XDR.
6.1. Code Components Licensing Notice
Both the XDR description and the scripts used for extracting the XDR
description are Code Components as described in Section 4 of "Legal
Provisions Relating to IETF Documents" [LEGAL]. These Code
Components are licensed according to the terms of that document.
7. Security Considerations
There are no new security considerations beyond those in [RFC7862].
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8. IANA Considerations
There are no IANA considerations.
9. Normative References
[LEGAL] IETF Trust, "Legal Provisions Relating to IETF Documents",
November 2008, <http://trustee.ietf.org/docs/
IETF-Trust-License-Policy.pdf>.
[RFC1813] IETF, "NFS Version 3 Protocol Specification", RFC 1813,
June 1995.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4506] Eisler, M., "XDR: External Data Representation Standard",
STD 67, RFC 4506, May 2006.
[RFC5661] Shepler, S., Ed., Eisler, M., Ed., and D. Noveck, Ed.,
"Network File System (NFS) Version 4 Minor Version 1
Protocol", RFC 5661, January 2010.
[RFC7862] Haynes, T., "NFS Version 4 Minor Version 2", RFC 7862,
November 2016.
[RFC7863] Haynes, T., "Network File System (NFS) Version 4 Minor
Version 2 External Data Representation Standard (XDR)
Description", RFC 7863, November 2016.
[RFC8178] Noveck, D., "Rules for NFSv4 Extensions and Minor
Versions", RFC 8178, July 2017.
[RFC8435] Halevy, B. and T. Haynes, "Parallel NFS (pNFS) Flexible
File Layout", RFC 8435, August 2018.
Appendix A. Acknowledgments
Trond Myklebust and David Flynn all worked on the prototype at
Hammerspace.
Appendix B. RFC Editor Notes
[RFC Editor: please remove this section prior to publishing this
document as an RFC]
Haynes & Myklebust Expires January 26, 2020 [Page 14]
Internet-Draft Deleg Stateid July 2019
[RFC Editor: prior to publishing this document as an RFC, please
replace all occurrences of RFCTBD10 with RFCxxxx where xxxx is the
RFC number of this document]
Authors' Addresses
Thomas Haynes
Hammerspace
4300 El Camino Real Ste 105
Los Altos, CA 94022
USA
Email: loghyr@hammerspace.com
Trond Myklebust
Hammerspace
4300 El Camino Real Ste 105
Los Altos, CA 94022
USA
Email: trondmy@hammerspace.com
Haynes & Myklebust Expires January 26, 2020 [Page 15]
