At 15:00 2-8-2001 -0600, Steve Wolfe wrote:
> >I assume you mean software RAID5, right? I've got a RAID50 array: 28-port
> >3ware cards in hw raid5, then those two devices combined softwareraid0. I
> >didn't bother to make the log on a separate device, but I could,
> That is silly. Just make a big raid0 of it. If for some reason one ofthe
> 3ware cards takes a dump you WILL LOSE ALL YOUR DATA.
> Which is exactly the reason to avoid the above mentioned configuration.If
> one card dies you have just lost all your data.
Personally, I'd bet on a drive or two going out before the controller.
I haven't had any sort of drive controller (IDE/SCSI/RAID) go out in
nearly a decade, but I've had plenty of drives go South on me.
I have seen lots of drives go bad too. But don't discount Murphy. You might
just have a bad day and a firmware upgrade of your controller resets the
raid set. Most people with more then one 3ware card will set it up in JBOD
mode and then use it as a software raid5 with a external log.
> Which was exactly what happend. They raid
> controller (Ami megaraid) got upset after one disk died and they lost
> complete Mysql Database.
Since this isn't the place, I won't point out the obvious flaws in
their backup/recovery scheme.
What's a backup? And recovery is for wimps ;)
My experience with the MegaRAIDs has been
that the cards do work fine, provided that you do everything exactly the
way the card expects - which is sometimes complicated, sometimes
difficult, and usually counter-intuitive. ; )
Yup. I have screwed up raid sets before on our servers too.(during testing
and with backups).
I just feel that my data would not be safe with the setup that you have
provided. They even had bugs in the 3ware raid config which caused
corruption in degraded mode. If that happens on your raid0 array or any
array you are going to lose data. But I think that the chances of severe
damage will grow in this raid0 setup.
Every program has two purposes one for which
it was written and another for which it wasn't
I use the last kind.