Minneapolis Cluster Summit 2004


The first ever Mineapolis Cluster Summit took place in July this summer.  This was initially planned to be an informal workshop to bring GFS developers face-to-face and kick off community development of the GFS cluster filesystem suite, recently acquired and liberated by Red Hat.  Our little workshop grew into a meeting of over 50 prominent cluster developers from all over the world.

The summit workshop began on Thursday with Red Hat presentations of the (former) Sistina GFS cluster filesystem and cluster infrastructure, continuing to Friday morning.   On friday afternoon we moved on to presentations from other community cluster projects.  We concluded with a round table discussion on adapting GFS cluster infrastructure components for use by other projects, and how we will prepare for mainline kernel submission.  It is fair to say that much solid work was revealed to all participants, in many cases, for the first time.
  1. Summary by John Cherry
  2. Red Hat Cluster Infrastructure Overview
  3. GULM - User Space client/server cluster membership and lock service
  4. CMAN - Kernel cluster membership
  5. DLM - Kernel distributed lock manager
  6. Magma - User level Cluster and Lock manager transparent library
  7. GFS - Evolution and changes between GFS 4.2 to today
  8. Global Network Block Device (GNBD)
  9. CLVM - Architecture and extensions of LVM2
  10. Cluster Block Devices (Snapshot, Mirror)
  11. Cluster resource management
  12. OpenSSI
  13. SCRAT + Resource Agent API
  14. Linux HA
  15. Clustered samba
  16. Related Material

pictureSummary by John Cherry

John Cherry of OSDL wrote a summary for the OSDL mailing lists and kindly consented have it included here:
The summit was well attended.  Besides RedHat/Sistina, other open source
cluster projects were represented (linux-ha, OpenSSI) as well as
proprietary clusters projects and cluster filesystems (i.e. Lustre,

The meetings were primarly intended to inform the community about the
recently opened RHAT/Sistina clustering components (including clustered
LVM and GFS).

The time was right to consider common clusters components. While we
expected a fair amount of contention at the meetings, it was good to see
a fairly unanimous desire to identify common components that could be
leveraged over the various cluster implementations and to drive these
common components to mainline acceptance. The common cluster components
identified at the summit were...

cman - cluster manager (membership/quorum/heartbeat, recovery
fence - userland daemon which decides which nodes need fencing
dlm - fully distributed, fully symmetrical lock manager
gfs - clustered filesystem

While these common components all have RHAT/Sistina roots, these
components are in the best position for mainline acceptance. As APIs
are defined for these services, other implementations could also be used
(the vfs model).

It was felt that it would be best to leverage an existing mailing list
for discussions regarding the common cluster components, so
linux-cluster will be used for this. To subscribe...


The project page has links to the various components and can be found


The cluster community would like developers to start looking at the code
and testing it in their environments. Documentation, source code,
mailing lists, IRC, and key links can all be found on the project page.

John Cherry
CGL Roadmap Coordinator
Originally posted here.


Red Hat Cluster Infrastructure Overview

Presented by: Patrick Caulfield, Red Hat

Slides - Cluster Infrastructure
Slides - CLVMD


GULM - User Space client/server cluster membership and lock service

Presented by: Mike Tilstra, Red Hat

Slides - GULM Overview


CMAN - Kernel cluster membership

Presented by: Patrick Caulfield, Red Hat

Slides - CMAN


DLM - Kernel distributed lock manager

Presented by: Patrick Caulfield, Red Hat

Slides - GDLM


Magma - User level Cluster and Lock manager transparent library

Presented by: Lon Hohberger, Red Hat

(bonus feature: Supporting Red Hat's legacy cluster applications)

Slides - Magma Cluster Library


GFS - Evolution and changes between GFS 4.2 to today

Presented by: Ken Preslan, Red Hat

Slides - GFS Evolution


Global Network Block Device (GNBD)

Presented by: Ben Marzinski, Red Hat

Slides - GNBD Overview

Other useful GNBD documentation:

GFS 6.0 Administrator's Guide (outdated, but most of the information is still correct)

Amir's GNBD usage page (Current)

GNBD man pages Somewhere between 6.0 information and Current. This is available with the code (cluster/gnbd/man/*).

The documentation will be updated shortly.


CLVM - Architecture and extensions of LVM2

Presented by: Alasdair Kergon, Red Hat

Nothing here yet


Cluster Block Devices (Snapshot, Mirror)

Presented by: Daniel Phillips, Red Hat

Slides - It's all done with Smoke & Mirrors

Slides - Cluster Snapshots


Cluster resource management

Presented by: Lon Hohberger, Red Hat

Slides - Cluster Resources



Presented by: Bruce Walker, HP

Slides - Linux SSI

Sourceforge Project Page



SCRAT + Resource Agent API

Presented by: Lars Marowsky Bree, Suse/Novell

SCRAT White Paper


Linux HA

Presented by: Alan Robertson, IBM

Slides: Evolution


Clustered samba

Presented by: Chris Hertel, Samba team

Various interesting/nasty issues of event notification, case translation and database distribution were discussed.

CIFS conference slides - Samba Clustering with GFS
Samba Implementation - Read the book

"Samba moosed be clustered" -- Daniel
"Yes it moosed" -- Chris

Related Material

Presented by: Various

Cluster Summit Announcement
Cluster Summit Information and Schedule
Community Cluster Page
Slides from the Linux Cluster Infrastructure BOF at Ottawa Linux Symposium

Your Humble Organizers...

Matthew O'Kepictureefe

Daniel Phillips


And special thanks to

Brian Stevens


for making it all happen.

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