LSI 9261 question

[andrewbedia]

I've got a M1015 in another server in IR mode, and if a drive isn't part of a logical volume, it simply gets presented to the OS as a normal drive (can read smart data and all that jazz).

I have this much fancier LSI 9261-8i and it doesn't do this. Is there a way to have it present unconfigured drives to the OS as if it were connected as a HBA?

EDIT: trying this with Fedora 20 linux on a flash drive. It shows the controller in lspci

 

[Rhinox]

It is strange, but some LSI-controllers (even those middle/high-end) simply does not know "JBOD" so you can not present drives to OS "as they are", without intermediate raid-layer. But you can create raid0 even with 1 drive...

 

[PigLover]

1 drive Raid0 is not the same as JBOD. A drive in this configuration will have Raid Header written into physical block 0 rather than a partition table and then the "virtual" drive will start at block 1. This drive does not have data portability when it is removed and plugged into a single-drive connector or "real" jbod.

If the raid header written was "standard" and portable between controllers and controller vendors this might not be too big of a deal. But in general they are not.

This "issue" is a big deal for people running ZFS. One of the major features of ZFS - and one that has saved my ass at least twice - is the ability to export a pool of drives from one system and easily import them onto another. Having "pseudo jbods" using single-drive raid0 makes this a much less interesting/helpful feature.

 

[Rhinox]

1 drive Raid0 is not the same as JBOD...

Never said that. I just presented it as one option how to use single drive, if controller *does not* support JBOD...

 

[mobilenvidia]

LSI have recently removed JBOD support from their MegaRAID controllers
So only way for OS to see drive is via a single drive RAID0.
Its a pain as it taunts at boot up with splash screen reporting no JBODs found knowing full well you have one attached.

You can go back in firmware versions and have JBOD enabled

 

[andrewbedia]

Man, that is catastrophically silly. Makes it hard to run a destructive write test using badblocks (this is what I'm doing for a stack of drives that will be in a colocated server. found 3 dead so far).

EDIT: Guess I'll just toss the M1015 in there for the badblocks tests.

 

[mrkrad]

you haven't played with megascu.exe eh? you can expose drives as jbod with some foolin' around in the feature set, but you have to be careful.

 

[mobilenvidia]

You keep talking about this, but how does one do this ?

Simply setting the JBOD enable flag doesn't work anymore

 

[andrewbedia]

I concur. That was the first thing I tried from the preboot cli. Doesn't seem to do squat.

Put the M1015 in last night to start the badblocks.