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Subject: Re: Switching from MFI to MRSAS
To: Tim Gustafson <tjg@ucsc.edu>
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From: Michael Fuckner <michael@fuckner.net>
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Date: Wed, 23 Sep 2015 18:57:12 +0200
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On 9/23/2015 5:55 PM, Tim Gustafson wrote:
>> Different driver for different LSI Chipsets
>
> That's not what the man page says.  The man page says:
>
> "Older MegaRAID controllers are supported by mfi(4) and will not work
> with mrsas, but both the mfi(4) and mrsas drivers can detect and
> manage the LSI MegaRAID SAS 2208/2308/3008/3108 series of
> controllers."
>
OK, haven't done this before, perhaps this works, but... you are 
replacing a raid driver with another raid driver, so probably TRIM will 
not work either.

> So that's what I'm asking about.  I have a newer card, which according
> to the man page is supported by the mrsas driver.  So my question is,
> if I "flip the switch" so that the mrsas driver takes over, will
> everything "just" work, or will I need to re-format my disks because
> the "mfi" driver configures the disks in a way that is somehow
> incompatible with the "mrsas" driver.
the on disk format should be compatible.

Good luck,
  Michael!