[BBLISA] Fileserver opinion

[John P. Rouillard]

In message <BANLkTin=PQga7R4us208j5iZxD-eQy+JSA at mail.gmail.com>,
Daniel Feenberg writes:
>We have been using ZFS under FreeBSD for a while, and are very pleased,
>but are considering building a system with SAS drives, in the hope that they
>will be faster (any truth to that?). I am assuming that I should look for a
>non-RAID controller, but I can't find any SAS controllers that don't claim
>to do RAID and are on the FreeBSD compatibility list. I have always thought
>that using a RAID controller for a non-raid partition was a bad idea, since
>it limited ones ability to swap controllers. Is that prejudice justified?

Probably. Some raid controllers can be set to jbod/passthrough mode
which should eliminate any "raidish" remnants. I did set up a software
raid 10 on 3ware hardware with SATA disks in passthough mode and was
able to move it to a system using the motherboard SATA connectors and
get it working. YMMV.

But if the raid controller tries to manage the disk rather than just
say here it is they usually have their own format for the drives which
locks you into that brand controller if not a specific family of
controllers.

One thing we use at $WORK are lsi cards where we created a striped
(logical) volume/disk with a single physical disk. We did this when we
couldn't get jbod mode to work (or wasn't supported on the card). I
have no clue how/if I can reuse them without the lsi card.

--
				-- rouilj
John Rouillard
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My employers don't acknowledge my existence much less my opinions.