Gentoo Archives: gentoo-user

From: "Stefan G. Weichinger" <lists@×××××.at>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] hp H222 SAS controller
Date: Wed, 10 Jul 2013 17:12:54
Message-Id: 51DD9609.9040402@xunil.at
In Reply to: Re: [gentoo-user] hp H222 SAS controller by Alan McKinnon
1 Am 08.07.2013 23:42, schrieb Alan McKinnon:
2
3 > If it makes you feel better, then by all means go through the motions
4 > .
5 >
6 > For my money, I reckon that's exactly what it is - motions and ritual. I
7 > havew any anecdotal evidence to back it up, but it's fairly strong
8 > anecdotal evidence:
9 >
10 > Over the last 5 years, the team I'm in, the teams we work closely with
11 > and the Storage guys have commissioned >1000 pieces of hardware and
12 > probably more than 4000 drives, the vast majority from Dell. I have no
13 > idea what burn-in Dell applies, if any. We've had our fair share of
14 > infant mortality failures, prob ably less than 20 in 5 years. And here's
15 > the kicker - every single one failed in production.
16 >
17 > Most of that hardware, and ALL of the SANs, went through heavy
18 > pre-deployment testing. Usually, this means cloning the -dev system onto
19 > it and running the crap out of it for a decent length of time. Once the
20 > techies were happy, install the production version and switch it on.
21 >
22 > I conclude that the likely reason we only found failure in prod is that
23 > only prod gives a decent viable test that approximates real life and dev
24 > is always a mere simulation. It's not usage that kills a few drives
25 > early, it's the almost random pattern of disk access that you get in
26 > real life. That tends to shake out the weak links better than any test.
27 >
28 > However, this is all anecdotal so use or discard as you see fit :-). I
29 > no longer worry about data loss as we have 4 hour warranty turnaround
30 > SLAs in place and company policy is to only deploy storage that is
31 > guaranteed to survive loss of any one drive in an array.
32
33 Thanks for that, good point :-)
34
35 Stefan