[linux-lvm] Working together

[Mark Peloquin]

Hello everyone,

On behalf of the EVMS project (http://sourceforge.net/projects/evms or
http://oss.software.ibm.com/developerworks/opensource/evms) team, we
would like to invite the Linux LVM project to join/collaborate with our
project.  The goal of this collaboration is to offer a complimentary set of
functionality to the Linux community, rather than multiple sets of
functionality
that overlap and compete.

As many of you know, the EVMS project, in design and scope, is meant to
be a total Logical Volume Management solution, including support for the
emulation of other volume management systems.

The EVMS team would like the Linux LVM project team to consider assuming
responsibility for the Linux LVM emulation component in EVMS, as well as
participating, if you like, in other areas of the EVMS project. EVMS offers
many
areas for participation.

> Why should Linux LVM join the EVMS project ?

The EVMS project can offer some immediate solutions to current Linux LVM
issues.

- EVMS supports in-kernel reading/writing of metadata

- EVMS supports in-kernel discovery of volume groups and volumes

- EVMS can solve migration and coexistence issues.  By supporting a plugin
  design, both the original Linux LVM and the new Linux LVM (new on-disk
  format) plugins could be loaded and running simultaneously, making
  migration/coexistence a breeze.

- EVMS infrastructure virtually guarantees compatibility with future plugin
  modules allowing additional features to be added on top of the Linux LVM
  volumes and/or volume groups.

- EVMS currently supports generic snapshots (i.e. - snapshoting
   anything-to-anything under EVMS control)

> Why now ?

- The timing is right since, from reading the Linux LVM mailing list, we
can
   see that the Linux LVM on-disk format is undergoing some enhancements
   for better reliability and recoverability. The scope of these changes
may
   affect a good deal of the current Linux LVM code base. The timing of
these
   changes provides a convenient opportunity to also consider switching
over
   to the EVMS infrastructure.  Furthermore, we have code for an initial
set of
   LVM plugins that currently support in-kernel LV/VG activation, complete
   read & write support for existing Linux LVM volumes, and support for
   Linux LVM snapshots. This code could make a reasonable starting point
   for a transition to the EVMS infrastructure.

   To encourage you a little more, the EVMS project will be supporting
   emulation of the AIX Logical Volume Manager. We would be happy to
   offer the AIX disk format if you think that would be useful to your
effort
   to improve the Linux LVM on-disk format.

We hope you will join us as we look forward to working with you.

Thanks.

The EVMS Team