This article provides information about the Ubuntu 16.04 operating system and Dell's OptiPlex Desktop systems, using the Intel Matrix RAID setup.
Ubuntu 16.04 and the type of RAID used on our OptiPlex desktops is not a natural fit. The OptiPlex uses Intel Software to provide a version of RAID 1 or 0. Ubuntu is not setup by default to recognise this sort of RAID. Various issues branch off from this original issue. While you can upgrade to the latest LTS version, the OptiPlex series of desktops have been certified for use with Version 12.04 through to 16.04. Below we'll give information and links to workarounds and various installation steps to get around this RAID issue.
Ubuntu cannot be installed on a VHD (RAID 1 or 0) with the default setting of the partition table used by Ubuntu. If you setup a RAID configuration under the Intel Matrix Manager by pressing the CTRL+I function before boot and then start the machine from the Ubuntu LIVE media and start the installation - you will get an error on the next step Ubuntu cannot be installed on this partition.
Instead you need to setup the RAID partitions using the Intel Matrix Controller Interface and then carry on with the rest of the instructions below.
You need to start by configuring your Software RAID. Go to the Canonical article linked below and follow the instructions from the start of the article until it gets to the Bootloader Section :
In order to workaround this issue, you need to change the default setting to /dev/mapper/xxxxxxxx_Volume1 and set up the swap, Boot, and EXT4 partitions manually. Check out the article below on how to change this setting :
Please check out the guides below for further information on custom Ubuntu Installs :
Previously because the platform doesn't support VHD, the system failed to rebuild RAID1. If you replaced one of the two hard drives, the system would remain on rebuild status. If you reset the new hard drive in the RAID controller interface by pressing the CTRL+I function before the system boots and forcing the rebuild - it didn't have any effect. The RAID1 volume would remain on rebuild status.
If on the other hand we say that you have used the correct methods to install (As recommended in Section 2.) Ubuntu with the latest BIOS. Then we can recommend the following steps in order to resolve or test this particular issue :
In order to recreate a fault we can remove a hard drive from the array and reboot the machine.
The first thing is to check the system boots in degraded mode.
When in degraded mode there is only one hard drive active in the RAID1 group (most commonly md0). Where sdX is the inactive hard drive, the following command in Terminal (CTRL+ALT+T) can remove it from the RAID1 group :
If it boots fine add the hard drive back and the let the Operating System resync the RAID content.
To resynch the content from the active hard drive and recover the group, you can run the following command in Terminal (CTRL+ALT+T) :
To check the RAID status run this Terminal command (CTRL+ALT+T) :
It's been reported that some people using 12.04 can only see clone mode.
It's been advised that this can be resolved by moving from integral graphics to an add on PCI graphics card or by updating to Ubuntu LTS Version 14.04 or 16.04.
I've also linked to some articles below that go into Ubuntu Video in greater detail :
Article ID: SLN299297
Last Date Modified: 03/07/2019 07:53 AM
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