[Beowulf] RAID for home beowulf
a.travis at abdn.ac.uk
Sat Oct 3 16:46:41 PDT 2009
Mark Hahn wrote:
> redundancy costs - your only choice is what kind of redundancy you want.
> raid5 has its issues, but really what's needed is redundancy managed
> by the filesystem. doing it block-level is what introduces the pain.
You're right ;-)
I've just been reading about the Hadoop file system. That recommends not
using RAID at all, and just relying on configurable levels of redundancy
in the filesystem. However, I've got a complete mental block about using
the Hadoop filesystem 'shell'. I'll persevere, though because it does
look very interesting. I've been trying to learn how to use it for ages!
>>> 3) I'll leave the /boot partition on one of the 3 disks and it will NOT
>>> be included in the RAID array, is this ok?
>> I think you'd be better off putting your system one one of your three disks,
>> and making a RAID1 for /home from the other two. This will give you a
> I disagree. for one, I strongly advice against partition-o-philia:
> the somewhat traditional practice of putting lots of separate partitions
> on a system. but for 3 disks, linux MD has a nice mode where each block
> is stored twice. so you get 2/3 space efficiency and potentially better
I'm not quite sure I understand what you're saying here: I have my
system organised in such a way that my 3ware RAID's provide a bare-metal
recovery backup using just three partitions:
sda1 / 40GB
sda2 swap 8GB
sda3 /backup rest of disk
The 'md' RAID5 is four disks with a single partition:
sd[abcd]1 RAID autodetect
How is this "partition-o-philia"?
> MD software raid certainly can support HS - it's mainly a feature of the
> controller. (this is not to say that most controllers do HS well.)
I'm interested in that - It was only alpha release when I looked, and
not recommended for production use. I did some experiments, and settled
on hot-swap using the 3ware 8006-2's, with 'md' software RAID10.
Dr. A.J.Travis, University of Aberdeen, Rowett Institute of Nutrition
and Health, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
tel +44(0)1224 712751, fax +44(0)1224 716687, http://www.rowett.ac.uk
mailto:a.travis at abdn.ac.uk, http://bioinformatics.rri.sari.ac.uk/~ajt
More information about the Beowulf