# Error - RAID - Cannot  determine root /

## euduca

Hi.

In a few days, I'm trying to install the Gentoo in our server (parallel computing and performance tests and programs) . I can't do the Gentoo recognize the RAID1.

I'm  tired, but I don't wanna to give up. if I give up, my boss will want to install the Fedora in this server. =(

I did follow this wiki: http://en.gentoo-wiki.com/wiki/RAID/Onboard

And this post: https://forums.gentoo.org/viewtopic-p-4570091.html#4570091

And this: http://dev.gentoo.org/~neddyseagoon/kernel_conf/  :Arrow:  I did try this one: gentoo-sources-2.6.31-r4.config

The RAID Controller is Intel Corporation 82801JIR (ICH10R) SATA RAID Controller.

The Bios options are: 

Onboard SATA Controller [Enabled]

SATA MODE [SWRAID] - this is default (the others modes are: COMPATIBILITY, AHCI and ENCHANCED)

My gentoo option in boot at live cd is dodmraid.

```
livecd #  dmraid -s

*** Group superset .ddf1_disks

--> Active Subset

name   : ddf1_4c5349202020202080862925000000003926cced00001450

size   : 1951170560

stride : 128

type   : mirror

status : ok

subsets: 0

devs   : 2

spares : 0

```

I used the cfdisk to make my partitions:

```

                                                            Device Boot      Start         End      Blocks   Id  System

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p1   *           1          24      192748+  83  Linux

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p2              25       14963   119997517+  83  Linux

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p3           14964       29902   119997517+  83  Linux

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p4           29903      121454   735391440    5  Extended

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p5           29903       30898     8000338+  82  Linux swap / Solaris

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p6           30899       33388    20000893+  83  Linux

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p7           33389      121454   707390113+  83  Linux

```

Partitions:

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p6   /

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p1  /boot

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p2  /usr 

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p3 /var

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p5 swap 

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p6 /opt

(chroot) livecd / # ls /dev/sda*

/dev/sda  /dev/sda1  /dev/sda2  /dev/sda3  /dev/sda4  /dev/sda5  /dev/sda6  /dev/sda7

(chroot) livecd / # ls /dev/sdb*

/dev/sdb  /dev/sdb1  /dev/sdb2  /dev/sdb3  /dev/sdb4  /dev/sdb5  /dev/sdb6  /dev/sdb7

I mount the partitions to install the Gentoo base system. And I follow the handbook to continue installing  the Gentoo in the HDs.

```

livecd ~ # df -h    

Filesystem            Size  Used Avail Use% Mounted on

tmpfs                 7.9G  331M  7.6G   5% /

/dev/sr0              2.7G  2.7G     0 100% /mnt/cdrom

/dev/loop0            2.6G  2.6G     0 100% /mnt/livecd

udev                   10M  220K  9.8M   3% /dev

cachedir              4.0M  160K  3.9M   4% /mnt/livecd/lib64/splash/tmp

tmpfs                 7.9G  6.1M  7.9G   1% /mnt/livecd/lib64/firmware

tmpfs                 7.9G     0  7.9G   0% /mnt/livecd/usr/portage

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced000014506

                       19G  420M   18G   3% /mnt/gentoo

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced000014501

                      183M   20M  154M  12% /mnt/gentoo/boot

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced000014502

                      113G  3.6G  104G   4% /mnt/gentoo/usr

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced000014503

                      113G  236M  107G   1% /mnt/gentoo/var

/dev/mapper/ddf1_4c5349202020202080862925000000003926cced000014507

                      665G  198M  631G   1% /mnt/gentoo/opt
```

After all, I reboot the system. And the problems appears.

I'm trying to use the /dev/mapper/ddf1_4c5349202020202080862925000000003926cced00001450p1 as real_root  in grub, but the address change in each boot.

boot

ddf1_4c53492020202020808629250000000039250214000014506

after reboot

ddf1_4c5349202020202080862925000000003925070c000014506

after reboot

ddf1_4c53492020202020808629250000000039250c4c000014506

My grub.conf:

```
title Gentoo Linux kernel-x86_64-2.6.32-gentoo-r7

root (hd,0,0)

kernel (hd0,0)/kernel-genkernel-x86_64-2.6.32-gentoo-r7 root=/dev/ram0 real_root=/dev/mapper/RAID_PARTITION init=/linuxrc ramdisk=8192 dodmraid udev

initrd (hd0,0)/initramfs-genkernel-x86_64-2.6.32-gentoo-r7

```

If I exclude the option "dodmraid" in grub, and use /dev/sda6 as real_root; the system boot properly, but I think this won't work, because if I create a file in /dev/sda6, and after I mount the /dev/sdb6, the file doesn't exist in there. I have access in the disk, but I think the RAID doesn't work.

So... I'm sorry for my poor english.

I'm using the Gentoo for 3 years, and this problem is being very difficult  to me.

Thanks, Duca.

----------

## euduca

Do I need to create the RAID partitions using the mdadm?

Duca.   :Surprised: 

----------

## frostschutz

You don't /have/ to use mdadm, but unless you're using a dedicated hardware raid controller pcie card (like 3ware etc), I'd suggest you use mdadm since it's the best software raid solution around...

Also, if your board (and therefore your raid controller) ever dies you can just put the disks into a different machine and it'll still work.

As for the device changing its name, you'd probably have to use UUID then... it should be supported by Gentoo's initrd.

----------

## euduca

Hi frostschutz.   :Surprised: 

Thanks for helping.

I don't have success with the Intel Corporation 82801JIR (ICH10R) SATA RAID Controller, in my Gentoo system.

Today. I have success in a server with Intel Corporation 82801 SATA RAID Controller (ICH9R),  just following this tricks:

http://en.gentoo-wiki.com/wiki/RAID/Onboard

https://forums.gentoo.org/viewtopic-p-4570091.html#4570091

```
kraken ~ # cat /etc/gentoo-release 

Gentoo Base System release 1.12.13

kraken ~ # eselect profile show

Current make.profile symlink:

  default/linux/amd64/10.0 

```

```
kraken ~ # dmraid -s

*** Group superset isw_jdeejigjf

--> Active Subset

name   : [b]isw_jdeejigjf_RAID1[/b]

size   : 488390912

stride : 128

type   : mirror

status : ok

subsets: 0

devs   : 2

spares : 0

```

```
# df -h    

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/isw_jdeejigjf_RAID16

                       19G  416M   18G   3% /

udev                   10M  264K  9.8M   3% /dev

/dev/mapper/isw_jdeejigjf_RAID11

                      183M   14M  160M   8% /boot

/dev/mapper/isw_jdeejigjf_RAID12

                       76G  2.8G   69G   4% /usr

/dev/mapper/isw_jdeejigjf_RAID13

                       38G  1.5G   35G   4% /var

/dev/mapper/isw_jdeejigjf_RAID17

                       91G  188M   86G   1% /opt

shm                  1004M     0 1004M   0% /dev/shm
```

I did try to install in the other server: the Fedora 12, RH Enterprise and Debian.  The all distros doesn't recognize the RAID Controller.

The RH Enterprise locate the RAID path: dev/mapper/ddf1_4c5349202020202080862925005345545926cced00001450p and install the O.S. in the server, but after the reboot it crashes, because the path changes too. ¬¬

I'll try to update the Intel Corporation 82801JIR (ICH10R) SATA RAID Controller's firmware, now  :Exclamation: 

Thanks, Duca.

----------

## drescherjm

 *Quote:*   

> I don't have success with the Intel Corporation 82801JIR (ICH10R) SATA RAID Controller, in my Gentoo system.

 

Use mdadm instead unless you are dual booting with windows. That is not a hardware raid controller and there is no advantage to using it over mdadm.

----------

## gr0x0rd

I just set up RAID on a gentoo server with an ICH7R fakeraid controller, and I agree with John, you're probably better off with a software RAID configuration than fighting with it unless you are dual booting with windows, and this isn't ideal for any server...

The guide I followed is http://en.gentoo-wiki.com/wiki/Software_RAID_Install.

Good luck!

----------

## euduca

Hi everyone.   :Smile: 

I got it.

I did use the Intel Server Board S5520UR.

It contains a bootable Linux image, and after the boot it shows many options about the system and updates.

I created the RAID with this CD. 

I can adjust the device's name with the Web Console 2 (runs in loopback address). It show the RAID's properties, and its parameters.

When I created the RAID with the Intel's CD the name doesn't change after the reboot.   :Wink: 

If  I use the "Embedded RAID Configuration" (CTRL+E, during the boot) to create the RAID, the device's name change after each reboot.   :Confused: 

Thanks, Duca.    :Mr. Green: 

----------

## drescherjm

Don't do that. Create the array properly in linux before you properly install gentoo. Learn how to use the correct tool.

https://raid.wiki.kernel.org/index.php/Linux_Raid

----------

## euduca

But, in my case I want to use the Hardware's RAID. 

If I follow this link: https://raid.wiki.kernel.org/index.php/Linux_Raid, I will configure my raid with software's RAID. Am I right?

Thanks,.Duca

----------

## drescherjm

Sorry. I see that this is a HW SAS controller. Or at least Intel claims it to be HW raid. To lock down the drive devices you need to write a udev rule.

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## euduca

No problem!   :Very Happy: 

----------

