Software RAID5

[Gabriel Dragffy]

On 22 Sep 2007, at 08:42, Roland Smith wrote:

> On Fri, Sep 21, 2007 at 11:50:58PM +0100, Gabriel Dragffy wrote:
>> Hi all
>>
>> Hoping to get some help setting up software RAID5. Guides on the  
>> internet
>> seem to be few and far between, and official documentation is a  
>> little too
>> technical. Basically I have 3 x 500GB hard drives which I'd like  
>> to have in
>> a raid5 configuration, using software, root partition on their too  
>> would be
>> a bonus. I'd be grateful for assistance.
>
> What you need for RAID5 is gvinum(8), which replaces the older vinum 
> (4)
> driver.
>

Hi, reading the BSD Handbook I did find this out and I've been trying  
to use it.

> If you google for gvinum you'll find tutorials etc.

I have found a couple of tutorials but like I said it is either too  
technical, or not descriptive enough and none of them describe root  
on raid 5 :(

>
> AFAICT, you can't have the root device on a RAID5 gvinum. Just make a
> small root partition.

I read in the FreeBSD hanbook that I can have root on raid 5 by doing  
the following:
"There is another option as well, to have /boot/loader (Section  
12.3.3) load the vinum kernel module early, before starting the  
kernel. This can be accomplished by putting the line:
geom_vinum_load="YES"
into the file /boot/loader.conf."

This was on the following page: http://www.freebsd.org/doc/ 
en_US.ISO8859-1/books/handbook/vinum-root.html

The handbook is good, but it only describes how to do raid 0 and raid  
1, it says I can do raid 5 but doesn't describe the process. I also  
totally stumped at how to make a raid 5 device and install freebsd on  
it - the sysinstall doesn't allow the configuration of raid arrays  
and I can only install to a slice. I need access to tools such as  
gvinum before installation... but how? Oh the pain!

best regards

gabriel



>
> Roland
> -- 
> R.F.Smith                                   http://www.xs4all.nl/ 
> ~rsmith/
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