Re: Which RAID Controllers to pick/avoid?

Dan Birken wrote:
> - Is the supercap + flash memory considered superior to the BBU in
> practice?  Is that type of system well tested?

The main risk is that it's a pretty new approach.  The standard BBU
setup has been used for a long time now; this whole flash+supercap thing
has only showed up in the last couple of years.  Theoretically it's
better; the #1 weakness of the old battery setup was only surviving an
outage of a few days, and storing to flash doesn't have that issue.
It's just got the usual risks of something new.

> - Is the linux support of the LSI and Adaptec cards comparable?

Seems to be.  The latest versions of Adaptec's arcconf utility even
provide about the same quality of command-line tools as LSI's megactl,
after being behind in that area for a while.  Only quirk, and I can't
say where this was the manufacturer of the box or not because they
installed the base OS, is that the 5405 setup I saw didn't turn off the
write caches on the individual drives of the system.  That's the
standard safe practice and default for the LSI cards.

--
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