Re: 2.0.29 and maximum number of user.
H. Peter Anvin (hpa@transmeta.com)
11 Sep 1997 03:29:59 GMT
Followup to: <199709100137.UAA31253@mama.indstate.edu>
By author: Tall cool one <ice@mama.indstate.edu>
In newsgroup: linux.dev.kernel
> >
> > BUZZZZ!!! Wrong. If you have 8 drives with a MTBF of 250,000 hours then
> > the MTBF of a raid0 array is: 31250.. 1/8th.. A raid5 makes a failure
> > virtually impossible.. (Of course someone could rm -r /; or kill the
> > controler.. The controler can be replaced, and thats why there are tapes).
>
> Yada yada yada, of course, lightning never strikes, computers never get
> wet, etc, etc, etc... You still have to back things up, although raid5 does
> save you lots of time and frustration when a single drive does fail, which
> will be the majority of cases. Of course while that drive is out, unless you
> have a replacement sitting on your shelf, you're operating at raid0. The
> cost of raid5 then is not just the extra parity drive, but its replacement.
>
raid0 does have its uses, though. For example, if you're mirroring
a major FTP site, you typically don't really care if the data gets
lost, since it is only a replica anyway. That is, unless you're
relying on the data being there at all times.
-hpa
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