On Mon, Apr 13, 2015 at 8:10 AM, James M. Pulver <[log in to unmask]> wrote:
> I would point out that I'm not sure I've ever really seen the benefit of "Real Raid" except  for the vendor making more money. The only place I've used it is in iSCSI boxes that run everything in firmware.

The ability to properly RAID the boot partition, with "/boot" on it,
has been a big deal. In the way back when days of LILO, it was handled
by writing the very small boot loader to both disks of a RAID 1 array,
but could be a flipping nightmare with RAID 5 allocating and
remembering to allocate and write it to *every individual disk*. And
with grub, it's gotten more complex for Linux releases and RAID
systems that can't ensure that /boot/grub is on all the relevant
disks. It's been worth the tradeoffs for the flexibility, but there
are still features I miss from LILO.

Cleaning up after a mess like "the first disk got a screwed up boot
loader from disk failure or keyboard error" can be pretty expensive in
downtime, and engineering time and arranging remote hands-on support
in places where you didn't think you needed it "because you've got
RAID, and that protects you from disk failures".

> On all computers / servers, I've always used MDADM on Linux and ZFS on FreeNAS. Both have been excellent for my intended use, though FreeNAS is only at home for ~3 concurrent users, so take that whole thing with a grain of salt. Neither has lost data due to power outages or drive failures.

Have you worked out how to handle "/boot" other than to ignore it, the
way most people setting up software RAID do?