Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 7 Sep 2016 10:21:32 +0200
From:      Borja Marcos <borjam@sarenet.es>
To:        Dmitry Morozovsky <marck@rinet.ru>
Cc:        Mike <the.lists@mgm51.com>, freebsd-fs@freebsd.org
Subject:   Re: Recommended HBA for ZFS, contemporary
Message-ID:  <CFEDCDAB-26BC-4B38-B866-44A69AAAA8DE@sarenet.es>
In-Reply-To: <alpine.BSF.2.00.1608222136270.83952@woozle.rinet.ru>
References:  <alpine.BSF.2.00.1608221904270.82304@woozle.rinet.ru> <306ccab3-4c78-751a-2258-54701a64ab4b@internetx.com> <41DE4DAA-B5E1-4BB9-AF54-780236A901EF@gmail.com> <e9abbe16-837d-027a-6f0b-819944434143@mgm51.com> <alpine.BSF.2.00.1608222136270.83952@woozle.rinet.ru>

next in thread | previous in thread | raw e-mail | index | archive | help

> On 22 Aug 2016, at 20:36, Dmitry Morozovsky <marck@rinet.ru> wrote:
>=20
> On Mon, 22 Aug 2016, Mike wrote:
>=20
>>>> LSI SAS 2008 Based HBA, there are dozens of OEM available for =
Budget Prices
>>>=20
>>> With the IT firmware.
>>=20
>> What's the significance of "IT firmware"?
>=20
> ability to export raw disk device withou unnatural intelligence of a =
controller=20
> to mangle with data :)

That=E2=80=99s a serious problem with other HBAs, which are designed as =
=E2=80=9CRAID=E2=80=9D cards. That means you need
some effort to have them give you direct, CAM access to the disks.

The LSI2008 with IR firmware, however, is a different beast. It=E2=80=99s =
an HBA with an add-on RAID thingy. Provided
you don=E2=80=99t create logical volumes on it, the mps(4) driver will =
just make it behave like a simple HBA, which is excellent.

Although some claim that there is a performance difference between IR =
and IT firmware on the same card, according to
the helpful LSI guys in freebsd-scsi the difference should be =
negligible.=20

Anyway in case you want to cross flash from IR to IT it=E2=80=99s =
possible, although unsupported by LSI. However, sas2flash
checks wether the card is running IT or IR firmware and it will abort =
cross flashing attempts, except that at least
one old version does not abort and lets you proceed.

The procedure is described in a rather religious manner (religious =
because they don=E2=80=99t say that a particular
version is needed, nor why) here:

http://forums.overclockers.com.au/showthread.php?t=3D1045376

If I remember well I tried a LSI utility from the same date more or =
less, and it worked as well. More recent versions of sas2flash will
fail, however.

Cheers,




Borja.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CFEDCDAB-26BC-4B38-B866-44A69AAAA8DE>