Ubuntu 12.04 won't see raid 0

[offerlam]

Hi all,

Server: HP310e Gen8
disks: 4 3TB disk in raid 0 (I know the risks!!)
OS: Ubuntu server 12.04.2

When i set up the disk in a raid 0 my ubuntu installation still see each 3TB disk seperatly..??

In other words in does not see the logical raid 0

what do i do? I thought the 310e Gen8 was certified??

/Casper

[albandy]

Hi all,

Server: HP310e Gen8
disks: 4 3TB disk in raid 0 (I know the risks!!)
OS: Ubuntu server 12.04.2

When i set up the disk in a raid 0 my ubuntu installation still see each 3TB disk seperatly..??

In other words in does not see the logical raid 0

what do i do? I thought the 310e Gen8 was certified??

/Casper

Probably your raid device is a fake raid device. For example, My HPZ600 Workstation has a fake raid device:

00:1f.2 RAID bus controller: Intel Corporation 82801 SATA Controller [RAID mode]

and disk are detected separately
So there is no difference between doing a software raid or a fake raid.

But for example, my HP380-DL G7 has a real raid device:
05:00.0 RAID bus controller: Hewlett-Packard Company Smart Array G6 controllers

And is detected as raid.

[darkod]

If you are not using a dedicated card, +1 for using mdadm SW raid. Much better than any fakeraid unless you plan to dual boot (can't see much point dual booting a server).

But even if it's only a fakeraid it should detect it and ask you to activate it during installation. If you did the installation first and the raid later, you might need to activate it running from the server OS booted up:
sudo dmraid -ay

[offerlam]

Hey Guys,

I came to the same conclusion and im currently explorering the software raid option..

I will post back how it goes..

If any can supply a guide for Ubuntu server 12.04.2 it would very much appreciated since the one i could find was for version 9 dot something..

Thanks!

Casper

[darkod]

You need to suppy some info.

1. Are you installing the desktop OS but plan to run the machine as server, or the server OS?
The server cd has mdadm included, the live desktop cd. The install with mdadm raid will be different depending what you are installing.

2. You are looking for a guide for creating mdadm arrays or general ubuntu server guide?

I don't have any recent mdadm guides since using the server cd is very intuitive, and doing it on the command line with the live cd is very easy too.

The 12.04 LTS server documentation is here:https://help.ubuntu.com/12.04/serverguide/index.html

It mght include mdadm instructions in the Installation section, etc.

[offerlam]

Hey guys

After many attempts to get software raid up and going (im not linux expert) we have chosen to go ahead a buy a dedicated controller card instead .. this should work? as fare as i know I get this problem because im using the HP 310e gen8 onboard controller

Thanks for all your help!!

Casper

[darkod]

The onboard controller should allow you not to use raid, only to pass the disks. Same like the desktop motherboards that have raid option but you don't have to use it if you don't want to.

Are you sure you were trying to set up the mdadm raid correctly? Where did it fail?

[offerlam]

Darkod i think you misunderstand my post..

I ment that the onboard HP raid controller og the HP server. I'm not talking about the Linux software raid.

What started all this was that i made the raid through the HP onboard disc controller but that wasn't reconized by the Ubuntu installation.. so i had to turn to software raid.. i can't get it to work.. or my boss my won't give me the time to get it to work since its much cheaper to just but a dedicated controller card to use for hardware raid.. which allso performs better than software raid..

Casper

[darkod]

That's exactly what I meant. mdadm is very easy to make it work. Where did it fail?

A dedicated raid card might seem like the easy way out, but apart from additional cost you are also tying yourself up to a particular hardware card. For example, if it dies, you need to use the same model to get your array working and even then it might fail.

With SW raid you can read it on any linux machine, not only ubuntu.

But at the end of the day, the choice is all yours (or your boss's).

[offerlam]

It fails in the sense that i don't know what i'm doing... can you give me clear good guide to setup a raid 5 using software raid and 4 disc in a single patition which i then can install ubuntu server on...

I have created raids and all that but im sure how to partition them. Actually i was expecting that you had to make your raid and then install ubuntu on it and that was it..

I know the subject says raid 0 but that was with the HP controller which can't provide raid 5 - with the software raid i can..