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On Fri, 2009-10-09 at 13:32 -0600, Brendan wrote:
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On 10/09/2009 09:32 AM, Andres Paglayan wrote:
> now I just ordered the hardware, since the chassis supports 8 disks, and
> the mobo 6,
> so I purchased 8 disks just to have two identical spares sitting there
> unplugged.
Two port SATA controllers are $20. Pick one up and get those spares active.
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thanks for the good duh moment for me,
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> This means that I'll have 6 disks running on the machine,
> the server does constant little writes, and probably 50 times more
> little reads.
> mostly from the DB
Since you have more disks I'll renew my suggestion that you use one set
for DB and another for other IO modes.
> Since I don't see myself changing or adding disks during the life of the
> server,
> I will not do LVM on top.
That's too bad. LVM snapshots are freaking awesome.
> three mirrored groups of two, and then stripping, raid 10 (3/6
> available, 2 or 3 can fail)
Uh, parser error. Are you saying raid10(raid1,raid1,raid1)? Or are you
saying raid0(raid1,raid1,raid1)? The former means you can lose between
2 and 4 drives and keep going. The latter means, in theory, 2 drives
dying could lose data. Remember that you can do RAID1 with more than 2
disks. A 3 disk mirror means you have 3 copies of each drive. It's a
little brute force, but it works.
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I meant tree sets of mirrored pairs, then those three sets stripped,<BR>
but now I see that having two in the same set means death,<BR>
so a no go,<BR>
the three disk mirror option makes 2/6 available so another no go,<BR>
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> raid 6 (4/6 available, 2 can fail)
Yep.
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with other two alive, probably raid 6 with two hot spares is not a bad idea,<BR>
or as suggested, having two groups, one dedicated for the db, <BR>
and other for the rest of the file system<BR>
<BR>
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