Robroy - UFS/ZFS on Hardware RAID


Good day Kris and Allan!

I've split my question in to a quick edition and a detailed edition, in case the details are too long to read during your show.


Quick Edition
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If stuck with eight disks on an LSI 9268-8i (hardware RAID), which option is more likely to keep data safe and available:  A:  ZFS RAIDz2 on eight LSI RAID 0 virtual disks, or B:  UFS on one LSI RAID 6 virtual disk?


Detailed Edition
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A comrade and I would like to use ZFS on disks attached to an LSI 9268-8i, which has no IT mode firmware, and no JBOD mode.  'seems that a single RAID 0 virtual disk for each physical disk's as close as it gets.

This card's cache is set to write-through mode, and its patrol scrub is disabled.  The card has no BBU.

On page six of FreeBSD Mastery: ZFS, I read, "Do not use a hardware RAID controller.  Ever."

Two pages later, I read, "If you're condemned to use hardware RAID, probably because you were a very bad person in a previous life, present the operating system with single disks. If the RAID controller insists on formatting each drive as RAID-0, you're stuck."

Having read this--especially the first part--we spent several days trying hard to replace the 9268-8i with a 9211-8i.  Yet our computer refuses to recognize the new card; it only accepts the 9268-8i.  This is a Hitachi CR220H; the same 9211-8i worked fine in a Supermicro, but we have to use the Hitachi.

Given that we're stuck with the 9268-8i, which of these two options is most likely to keep our data safe and available long-term?

   A]  ZFS:  make an LSI RAID 0 virtual disk for each physical disk,
       then use the virtual disks for a RAIDz2 vdev.

   B]  UFS:  make a single LSI RAID 6 virtual disk, then use UFS
       on top.

I opened this FreeBSD Forums thread.  So far, all respondents who chose between these options, chose UFS (B) over ZFS (A).  I'd love to know your opinion.

   https://forums.freebsd.org/threads/57112/

Thanks so much!
Robroy