[dm-devel] [PATCH] libmultipath: update 3PARdata builtin config

[Xose Vazquez Perez]

On 06/29/2017 04:57 PM, Benjamin Marzinski wrote:

>>> +		.fast_io_fail  = 10,
>>> +		.dev_loss      = MAX_DEV_LOSS_TMO,

> On Wed, Jun 28, 2017 at 07:48:38PM +0200, Xose Vazquez Perez wrote:
>
>> It would be nice to have more information.
>> Why and when is this needed?
> 
> I assume the change to dev_loss_tmo is simply a preference issue. Like
> Netapp, they don't want their devices to get auto-removed when they go
> down. I also assume that in their internal testing, they hit cases where
> 5 seconds wasn't enough time to wait for some transient issue with the
> array to resolve.  At any rate, I'm simply passing along their request,
> which seems like a perfectly reasonable one to me.

Those arguments should come from the vendor.

"dev_loss_tmo 14" is recommended(???) in latest 3PAR docs (Jun 2017):

- HPE 3PAR SUSE Linux Enterprise Implementation Guide (Wed 14 Jun 2017 11:48:14 PM CEST)
   http://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay/?docId=c02663748

- HPE 3PAR Red Hat Enterprise Linux and Oracle Linux Implementation Guide (Wed 14 Jun 2017 12:10:06 AM CEST)
   http://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay/?docId=c04448818