cannot see /dev/sda during installation

[cncsc]

Hi guys,

I am currently having a problem with installing Ubuntu 12.04. I have a PC running Windows 7 and with 4 hard drives.

All partitions listed below:


Hard Drive A

Partition 1: 100MB, System Reserved (Win7 Required)
Partition 2: 100GB, Windows 7 OS
Partition 3: 670GB, Data 1
Partition 4: 162GB, free space for UBUNTU
Hard Drive B

Partition 1: 1TB, Data 2
Hard Drive C

Partition 1: 500GB, Windows Backup
Hard Drive D

Partition 1: 750GB, Data 3


The problem is when I go to the partition step and select "Something else" during installation, all partions are displayed as a list except partitions on HARD DRIVE A (there is no /dev/sda). So I am unable to get ubuntu installed. /dev/sda can be diplayed by using Gparted. It is really weird, because everything was fine on ubuntu 11.04 and earlier versions. Please help me.

[darkod]

If the disk has been used in raid, it has raid meta data remains. In this case ubuntu ignores it thinking you are using it in a raid array.

If you ARE NOT using any raid, remove the meta data from live mode with:
sudo dmraid -E -r /dev/sda

After that it should be fine. Usually this is the problem with these symptoms.

[cncsc]

If the disk has been used in raid, it has raid meta data remains. In this case ubuntu ignores it thinking you are using it in a raid array.

If you ARE NOT using any raid, remove the meta data from live mode with:
sudo dmraid -E -r /dev/sda

After that it should be fine. Usually this is the problem with these symptoms.

Thanks for your reply. I will try this once i'm back home.

[cncsc]

If the disk has been used in raid, it has raid meta data remains. In this case ubuntu ignores it thinking you are using it in a raid array.

If you ARE NOT using any raid, remove the meta data from live mode with:
sudo dmraid -E -r /dev/sda

After that it should be fine. Usually this is the problem with these symptoms.

This command works for me! Everything is OK now! Thank you again!:guitar::guitar: