On Jul 5, 10:46 am, Hajo Ehlers <serv...@metamodul.com> wrote:
> On Jul 4, 11:05 pm, Bernard Dhooghe <dhoog...@yahoo.com> wrote:
>
> > Actual vendor solutions not only have "descriptive" software but
> > also code that has to added and taken care of.
>
> MPIO for AIX does by default provides fail-over and an API for vendor
> solutions to provide enhanced functions such as load-balancing.
> To provide native MPIO support the OS has to know if the devices
> support such approach or not. For this reason you need an ODM
> extension.
> Example:
> EMC Clariion 600
> By default disk on this system are seen as "Other FC disk " and no
> MPIO support is given - meaning you see a disk for each path. In case
> you install the ODM package EMC.CLARiiON.fcp.MPIO.rte you will see
> only one disk for all pathes. In case you need load-balancing you have
> to install additional software from EMC
>
> > If DM-MM /DM-MPIO is a framework that can be used to unify, would
> > it not be nice to unify also in AIX?
> > Now for IBM storage products on AIX there is RDAC and SDD.
>
> IBM provides MPIO Support for SDD and DS4000 so these software should
> support MPIO.
> MPIO is the base where RDAC and SDD are the add-ons.
> All IMHO
>
> Reference:
> - DS4000 Best Practices and Performance Tuning Guide SG24-6363-03
> - Multipath Subsystem Device Driver User's Guide GC27-2122-00
>
> > On Linux I would expect the DS4000 to follow
> > the approach taken by SDD team but I could not find any
> > information about this.
>
> How about asking them ?
>
> regards
> Hajo

Hello Hajo,

The paper concerning SDD says that "SDD Linux will not be supported on
future releases so it is important that current SDD users understand
the differences between it and DM-MPIO." so from this, I understand
SDD vanishes, using new capabilities in Linux the storage vendor (here
IBM) can integrate with.

Concerning the DS4000, to ask certainly would be good, but whom?

Bernard (Dhooghe)