[CentOS] Anaconda doesn't support raid10

[Ruslan Sivak]

Ross S. W. Walker wrote:
>> -----Original Message-----
>> From: centos-bounces at centos.org 
>> [mailto:centos-bounces at centos.org] On Behalf Of Ruslan Sivak
>> Sent: Monday, May 07, 2007 12:53 PM
>> To: CentOS mailing list
>> Subject: [CentOS] Anaconda doesn't support raid10
>>
>> So after troubleshooting this for about a week, I was finally able to 
>> create a raid 10 device by installing the system, copying the 
>> md modules 
>> onto a floppy, and loading the raid10 module during the install. 
>>
>> Now the problem is that I can't get it to show up in anaconda.  It 
>> detects the other arrays (raid0 and raid1) fine, but the raid10 array 
>> won't show up.  Looking through the logs (Alt-F3), I see the 
>> following 
>> warning:
>>
>> WARNING: raid level RAID10 not supported, skipping md10. 
>>
>> I'm starting to hate the installer more and more.  Why won't 
>> it let me 
>> install on this device, even though it's working perfectly from the 
>> shell?  Why am I the only one having this problem?  Is nobody 
>> out there 
>> using md based raid10? 
>>     
>
> Most people install the OS on a 2 disk raid1, then create a separate
> raid10 for data storage.
>
> Anaconda was never designed to create RAID5/RAID10 during install.
>
> -Ross
>
>   

Whether or not it was designed to create a Raid5/raid10, it allows the 
creating of raid5 and raid6 during install.  It doesn't, however, allow 
the use of raid10 even if it's created in the shell outside of anaconda 
(or if you have an old installation on a raid10). 

I've just installed the system as follows

Raid1 for /boot with 2 spares (200mb)
raid0 for swap  (1GB)
raid6 for / (10GB)

after installing, I was able to create a raid10 device and successfully 
mount and automount by using /etc/fstab

Now to test what happens when a drive fails.  I pulled out the first 
drive - Box refuses to boot.  Going into rescue mode, I was able to 
mount /boot, was not able to mount the swap drive (as to be expected, as 
it's a raid0), was also not able to mount the / for some reason, which 
is a little surprising. 

I was able to mount the raid10 parition just fine. 

Maybe I messed up somewhere along the line.  I'll try again, but it's 
disheartening to see that a raid6 array would die after one drive 
failure, even if it was somehow my fault. 

Also assuming that the raid5 array could be recovered, what would I do 
with the swap partition?  Would I just recreate it from the space in the 
leftover drives and would that be all that I need to boot? 

Russ