Does anybody have experience with a MD1420, mpr(4)

[Lee Brown]

On Thu, Nov 16, 2017 at 6:28 AM, Kenneth D. Merry <ken at freebsd.org> wrote:

> On Wed, Nov 15, 2017 at 12:24:47 -0800, Lee Brown wrote:
> > Hi,
> >
> > This is my for foray into DAS, so please be gentle :)  Apologies if the
> > cross-post is inappropriate, let me know.
> >
> > I'm looking to build a SAS array with a Dell MD1420.  It will be attached
> > via a SAS 9300-414E HBA in a Dell R330.
> >
> > I've verified that the server / SAS card should be fine, but just wanted
> to
> > know if anybody has set this up before, or if there's any obvious reason
> > why it wouldn't work.  Dell can be a bit weird sometimes.
> >
> > Any information is most welcome.
>
> In theory it should be fine.  I haven't used a Dell enclosure recently, but
> from posts here, it seems that they like to turn on Type 2 Protection
> Information on the drives.  (Assuming you buy the drives from Dell.)
>
> If they do that, you can either reformat, or see the patch here for the
> mpr(4) driver to disable using protection information:
>
> https://docs.freebsd.org/cgi/getmsg.cgi?fetch=308820+0+
> archive/2017/freebsd-scsi/20171022.freebsd-scsi
>
> I haven't gotten around to changing things so that we detect the PI in the
> da(4) driver and use 32 byte CDBs when type 2 protection is enabled.  (So
> if someone else has time and wants to do it, feel free.  It will be
> somewhat messy because we only allocate enough space for 16 byte CDBs
> inside
> the CCB, so you'll need to allocate the CDB separately...)
>
> If you use ZFS, you'll have checksum protection on your data anyway, so PI
> would just be additional protection.
>
> I would also suggest that you update to the latest firmware (currently
> Phase 15) for the SAS controller.  You can do that with LSI's sas3flash or
> the FreeBSD mprutil(8) utility.
>
> Ken
> --
> Kenneth Merry
> ken at FreeBSD.ORG
>
Thanks Ken,

I'm going to purchase the system.  I had no idea about PI, that's a nice
feature for sure.

This will probably just be iSCSI and NFS4 over a 10Gb NIC (Xen cluster), so
having PI detection is certainly of interest to me.  I'll figure out what I
can do to contribute (code/testing) when things have settled.

Assuming all is well I'll get the 1420 added to the hardware compatibility
list.

Much appreciated -- lee