[dm-devel] [Consult] multipath-tools: will the community accept a new vendor specific path group prioritizer in libmultipath/prioritizers

[Hannes Reinecke]

On 12/11/2017 01:50 PM, Guan Junxiong wrote:
> Hi Christophe, Hannes, Martin, Xose and Benjamin,
> 
> It is beneficial for our customers if we integrate a new path group prioritizer into the multipath-tools.
> But this prioritizer is vendor-specific and it only works for Huawei storage system. Will the community
> accept such new vendor specific path group prioritizer in libmultipath/prioritizers?
> 
> I know that the multipath-tools accepted some vendor specific prioritizer such as emc.c , hp_sw.c, ontap.c and
> so on in the libmultipath/prioritizer in 2008~2010 and there were no newer vendor specific prioritizer.
> Before I get down to writing a new Huawei prioritizer, I want to hear your thoughts.
> 
> If it is convenient for some of you , please let me know your ideas. Thanks.
> 
The overall idea back then was that every new array would be using ALUA
to managing priorities, and that no new vendor-specific prioritizer
would be needed.

We know we have a deficiency if an array is connected via two distinct
transports (ie on path on FC and on path on iSCSI), as this should
affect priorities. But that should rather be handled in a generic level
and not in a vendor-specific manner.

So why do you think a vendor-specific prioritizer is required?
Does the Huawei array not support ALUA?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
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