[dm-devel] [multipath] SCSI device capacity mess

[Lars Marowsky-Bree]

On 2004-10-27T10:17:13, Lars Marowsky-Bree <lmb at suse.de> wrote:

> Using the new priority group initialization code (where we sent magic
> commands down to activate the newly switched-to PG) which Alasdair and I
> are currently doing for the CLARiiON pampering and which provides a
> plugin-architecture to the dm-mpath system, you should be able to plug
> in a hardware-specific handler for your system too.
> 
> However, "relaxing" this check should likely also be a property of the
> hardware plugin loaded; I'd not wish to have it relaxed in all
> scenarios.

-> have the hardware-specific plugin export a path_init() function which
is called the first time a path is added to the table (or even on
reinstate?).

In addition verifying the size and stuff it could also check that the
paths really (still) point to the same device (by storing the LUN WWN in
the hw_handler context, for example), or that the path is setup
correctly for failover to work etc (of course, the list of things to
verify is a hw-specific issue). Paranoia is a good thing.


Mit freundlichen Grüßen,
    Lars Marowsky-Brée <lmb at suse.de>

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