Diskconfig with RAID and LVM

[Tuan A. Tran]

Hi Michael,

Thanks very much. I googled and did some reading. They all suggested
that hardware RAID5 is a good choice. Generally speaking, I would hope
to get both speed and security. However, I would incline to get
security over speed.

Sincerely,
Tuan

On 4/15/05, Michael Tautschnig <michael.tautschnig at zt-consulting.com> wrote:
> > Hi all,
> >
> > I am a newbie in unix cluster as well as debian. My lab has a cluster.
> > The main server has RAID. There are 8 disks. The control card has a
> > bios. When it boots, I have an option to build a raid array (volume,
> > RAID0 (stripe), RAID5 or RAID10(stripes of mirror)). However, some of
> > these options (RAID5 and RAID10) were not regconized by Debian sarge
> > kernel (I think the kernel version is 2.6.9-k8). I got an image CD
> > build on Feb, 2005 for AMD64. Furthermore, Debian sees it as a single
> > SCSI. If at boot I build more than a single array, Debian would see
> > defferently. Since I am a newbie, I would like to have your opinions.
> > Should I do one of the following and which one is the best option?
> >
> The idea of hardware RAID - that is the one that is configured using the BIOS -
> that the operating system does not see anything but a single disk, everything
> else is managed by the hardware itself!
> 
> > 1) Install Debian and let Debian kernel control the raid on all 8 disks.
> > 2) At boot, using software make 4 arrays, then install debian and let
> > debian make an raid arrays from 4 scsi "disks"
> >
> If you got such a great controller, you should prefer the hardware-only
> solution. Actually I haven't got any idea why one would use software RAID in
> such a case.
> 
> > If you have better idea, I would really appreciate your telling me. A
> > concrete example would be great.
> >
> 
> Well, the question is - what is most important? Speed or security? How much
> diskspace is required? Using RAID 5 could provide the space of 7 disks, RAID10
> would only provide the space of 4 disks.
> 
> Regards,
> Michael
> 
>