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Re: [rddp] Storage Maintenance (storm) BOF reminder & requests

David, All,

While I am unfortunately unable to attend the BOF this week,
I am interested in contributing to

- RDDP MPA: Small startup update for MPI application support.

preferably through your Option (C), the "virtual" working group.


The interoperability of MPA-based RDMA connection management
is still a concern - for MPI, NFS/RDMA and other apps.

Because MPA has the (theoretically well-known) requirement that
the first FPDU be sent from the RDMA initiator side, whereas
InfiniBand has no such requirement, RDMA application writers
tend to be caught by surprise when an application that violates
this requirement works on InfiniBand but doesn't on iWARP.

The so-called "peer-to-peer connection management" that was
discussed in various flavours on the Linux OpenFabrics
reflector for making RDMA connection management more uniform
(among transports) and easier to use should be studied in detail.
The solution should be flexible enough to allow an optimized
application to avoid unnecessary additional round-trip delays.

In addition, MPA's "delayed startup sequence" (a.k.a. delayed
transition to RDMA mode or socket conversion) may need further
clarification. For instance, the negotiation of connection
parameters such as IRD and ORD should be clarified for cases
where Private Data is not used in MPA Request/Reply.
(IRD adjustment in RTS state is not mandatory according
 to the RDMAC Verbs, p. 74).


Besides contributing to draft text, I am interested in
early testing of the MPA startup update through a
software implementation.

- Fredy

Fredy Neeser, Research Staff Member
IBM Zurich Research Laboratory
Saeumerstrasse 4
CH-8803 Rueschlikon, Switzerland
e-Mail: nfd@xxxxxxxxxxxxxx
Phone : +41 (0)44 724 8487


From: Black_David@xxxxxxx
To: <ips@xxxxxxxx>, <rddp@xxxxxxxx>
Cc: imss@xxxxxxxx, Black_David@xxxxxxx
Date: 12.03.2009 00:29
Subject: [rddp] Storage Maintenance (storm) BOF reminder & requests
Sent by: rddp-bounces@xxxxxxxx

This is a reminder that the Storage Maintenance BOF will
be held in about 2 weeks at the IETF meetings in San Francisco.
Please plan to attend if you're interested:

THURSDAY, March 26, 2009
Continental 1&2                   TSV                   storm                    Storage Maintenance BOF

The BOF description is at:

The initial agenda is here:

I'm going to go upload that initial agenda as the BOF agenda,
and it can be bashed at the meeting.

The primary purpose of this BOF is to answer two questions:
(1) What storage maintenance work (IP Storage, Remote Direct
                Data Placement) should be done?
(2) Should an IETF Working Group be formed to undertake that

Everyone gets to weigh in on these decisions, even those who
can't attend the BOF meeting.  Anyone who thinks that there is
work that should be done, and who cannot come to the BOF meeting
should say so on the IPS or RDDP mailing lists (and it'd be a
good idea for those who can come to do this).  As part of the
email, please indicate how you're interested in helping (author
or co-author of specific drafts, promise to review and comment
on specific drafts).

Here's a summary of the initial draft list of work items:
- iSCSI: Combine RFCs into one document, removing unused features.
- iSCSI: Interoperability report on what has been implemented and
                interoperates in support of Draft Standard status for iSCSI.
- iSCSI: Add backwards-compatible features to support SAM-4.
- iFCP: The Address Translation mode of iFCP needs to be deprecated.
- RDDP MPA: Small startup update for MPI application support.
- iSER: A few minor updates based on InfiniBand experience.

Additional work (e.g., updated/improved iSNS for iSCSI, MIB changes,
updated ipsec security profile [i.e., IKEv2-based]) is possible if
there's interest.

There are (at least) four possible outcomes:
(A) None of this work needs to be done.
(B) There are some small work items that make sense.  Individual
                drafts with a draft shepherd (i.e., David Black) will
(C) A working group is needed to undertake more complex work
                items and reach consensus on design issues.  The WG can
                be "virtual" and operate mostly via the mailing list
                until/unless controversial/contentious issues arise.
(D) There is a lot of complex work that is needed, and a WG
                that will plan to meet at every IETF meeting should be

Please note that the IETF "rough consensus" process requires a
working group in practice to be effective.  This makes outcome
(C) look attractive to me, as:
- I'm coming under increasing pressure to limit travel, and
                the next two IETF meetings after San Francisco are not
                in the US.
- I'd rather have the "rough consensus" process available and
                not need it than need it and not have it available.

Setting an example for how to express interest ...

I think that the iSCSI single RFC and interoperability report are
good ideas, but I want to see a bunch of people expressing interest
in these, as significant effort is involved.  It might make sense
to do the single iSCSI RFC but put off the interoperability report
(the resulting RFC would remain at Proposed Standard rather than
going to Draft Standard), as I'm not hearing about major iSCSI
interoperability issues.

I think the latter four items (SAM-4 for iSCSI, deprecate iFCP
address translation, MPI fix to MPA and iSER fixes) should all
be done.

I plan to author the iFCP address translation deprecation draft,
and review all other drafts.

I think that a virtual WG should be formed that plans to do its
work primarily via the mailing list.  I believe the SAM-4 work
by itself is complex enough to need a working group - I would
expect design issues to turn up at least there and in determining
whether to remove certain iSCSI features, but I'm cautiously
optimistic that the mailing list is sufficient to work these
issues out (and concerned that travel restrictions are likely to
force use of the mailing list).


Ok, who wants to go next?

David L. Black, Distinguished Engineer
EMC Corporation, 176 South St., Hopkinton, MA  01748
+1 (508) 293-7953             FAX: +1 (508) 293-7786
black_david@xxxxxxx        Mobile: +1 (978) 394-7754
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