[K12OSN] Re: how's this raid setup?

[Robert Arkiletian]

On 9/2/05, Les Mikesell <les at futuresource.com> wrote:
> 
> On Fri, 2005-09-02 at 01:50, Robert Arkiletian wrote:
> 
> > So if sda failed, would the swap on the second drive shift?
> 
> First, note that they don't shift until the next boot. Then
> if one isn't available, you'll still boot and use any others
> listed in fstab. It will check that they really are swap
> partitions before using them. Also, md devices are normally
> autodetected anyway - the problem is more when fstab has
> entries for /dev/sdcn and they shift up to /dev/sdbn because
> an earlier device is missing.
> 
> > BTW I thought multiple swap partitions on seperate drives
> > automatically use raid 0. So do I need to state that they are a raid
> > device? Wait I just thought about this for a second. I think they HAVE
> > to be defined as a raid1 device. Assume you go into swap then one
> > drive fails. If it's raid0 you are going down bigtime!! So I think
> > they have to be explicitly defined as a raid1 device.
> 
> I've had some problems using disk druid to create the layout
> I wanted with multiple partitions on the same drives but it
> might be fixed by now. You should be able to create matching
> raid partitions on each drive, select them and create a raid
> device with the mount point and filesystem you want. The problem
> I've had is that the system re-arranges the positions on the
> disk so /boot isn't always first. If this happens you can
> nail down the layout by doing an fdisk first with the partition
> sizes you want and partition type of FD.
> 
> By the way, the current beta of SME server 7.x based on Centos4
> does a neat trick. If you install on a single drive it builds
> a 'broken' raid1 so at any time later you can add a 2nd drive
> and mirror the partitions to it.



Thanks for the explanation Les. I have just found a couple of nice PDF's I'd 
like to share with the list on this subject in case others are interested.

http://www.dell.com/downloads/global/power/1q04-hul.pdf
http://www.redhat.com/docs/manuals/enterprise/RHEL-4-Manual/pdf/rhel-sag-en.pdf(chap
9,10)

-- 
Robert Arkiletian
C++ GUI tutorial http://fltk.org/links.php?V19
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/k12osn/attachments/20050902/77e8adce/attachment.htm>