Ubuntu 9.04 Server Install with Software RAID1 and LVM

For the sake of reliability and flexability, I wanted to install Ubuntu 9.04 Server on a Dell PowerEdge using Software RAID1 (reliability) and LVM (flexability). Software RAID1 was also considerably cheaper (except for the time it took to figure this out) than adding in the $200 Dell SATA RAID contoller.

I consider myself to be a novice Linux/Ubuntu user, so feel free to blindly follow my actions.

Hardware

Dell PowerEdge T100
2 SATA Hard drives @ 160GB; No RAID Controller
8GB RAM

From the factory, the T100 comes with 2 primary partitions on the primary hard drive for utility/diagnostics purposes. I decided to keep the two partitions as they only use approximately 2GB space.

Installation

The Partition Disks section occurs after booting from the CD, setting up the keyboard, network, clock, etc.

Upon selecting a Partitioning Method of Manual, the following configuration is presented.

SCSI1 (0,0,0) (sda) - 160.0 GB ATA WDC WD1602ABKS-1
    #1 primary    41.1 MB        fat16
    #2 primary     1.5 GB        fat32
       pri/log   158.5 GB        FREE SPACE
SCSI2 (0,0,0) (sdb) - 160.0 GB ATA WDC WD1602ABKS-1
       pri/log   160.0 GB        FREE SPACE

The space needs to be split into two additional partitions on each physical disk. One partition will be for SWAP, the other for LVM. I have seen differing recommendations for SWAP sizes from 1.5 to 2.0 times the RAM.

For symmetry sake–I wanted to keep the partition IDs symmetric between drives–I added and removed some partitions to end up with the following.

SCSI1 (0,0,0) (sda) - 160.0 GB ATA WDC WD1602ABKS-1
    #1 primary    41.1 MB        fat16
    #2 primary     1.5 GB        fat32
       unusable  452.4 MB        unusable
    #3 primary   142.0 GB  B  K  raid
    #4 primary    16.0 GB     K  raid
SCSI2 (0,0,0) (sdb) - 160.0 GB ATA WDC WD1602ABKS-1
       pri/log   2.0 GB          FREE SPACE
    #3 primary   142.0 GB  B  K  raid
    #4 primary    16.0 GB     K  raid

When creating #3, specify:

Use as: physical volume for RAID
Bootable flag: on

When creating #4, specify

Use as: physical volume for RAID

The next step is to bind the partition pairs in a RAID1 configuration. To do this, select the Configure software RAID menu item, located above the disk partition information. You should get a dialog saying:

Before RAID can be configured, the changes...

When RAID is configured, no additional changes...

The partition tables of the following devices...

Write the changes to the storage devices and configure RAID?

Select Yes.

For each of the two partition pairs:
Select Create MD device
Multidisk device type: RAID1
Number of active devices for the RAID1 array: 2
Number of spare devices for the RAID1 array: 0
Active devices for the RAID1 multidisk device: /dev/sda3, /dev/sdb3 and /dev/sda4, /dev/sdb4 respectively

Select Finish to exit the multidisk config menu. The partition config should now include the following:

RAID1 device #0 - 142.0 GB Software RAID device
     #1            142.0 GB
RAID1 device #1 - 16.0 GB Software RAID device
     #1            16.0 GB

Change the properties of device #0 to:

Use as: physical volume for LVM

Change the properties of device #1 to:

Use as: swap

Next step is to Configure the Logical Volume Manager located at the top of the config. A dialog pops up with the following:

Before the Logical Volume Manager can...

After the Logical Volume Manager is...

The partition tables of the following devices are...

The following partitions are...

Write the changes to disks and configure LVM?

Select Yes.

LVM configuration action: Create volume group
Volume group name: vg
Devices for the new group: /dev/md0 (142001MB)

Now that the volume group has been created, we need to create the associated logical volumes.

For each partition you wish to create (/, /usr, /home, /opt, /var, /tmp, /srv) do the following steps:
LVM configuration action: Create logical volume
Volume group: vg (141998MB)
Logical volume name: root
Logical volume size: 5GB

Specify the volume sizes as you see fit. LVM how-to’s generally recommend that smaller sizes are better, as it is much easier to increase the size than decrease it.

After creating all the logical volumes, select Display configuration details:

Unallocated physical volumes:
  * none

Volume groups:
  * vg                                         (141998MB)
    - Uses physical volume:       /dev/md0     (141998MB)
    - Provides logical volume:    home         (4999MB)
    - Provides logical volume:    opt          (4999MB)
    - Provides logical volume:    root         (4999MB)
    - Provides logical volume:    srv          (49996MB)
    - Provides logical volume:    tmp          (4999MB)
    - Provides logical volume:    usr          (4999MB)
    - Provides logical volume:    var          (9999MB)

Select Finish to get back to the main partition config menu.

For each logical volume created, there is now an entry in the config:

LVM VG vg, LV home - 5.0 GB Linux device-mapper (linear)
     #1              5.0 GB

Select the #1 5.0 GB line and specify the following:

Use as: Ext3 journaling file system
Mount point: /home (respectively)
Label: home (respectively)

After all logical volumes have been configured, select Finish partitioning and write changes to disk. You will see a dialog:

If you continue, the changes listed below will...

WARNING:  This will destroy all data...

The partition tables of the following devices are...

The following partitions are...

Write the changes to disk?

Select Yes, and your install should continue as normal until you reach a screen titled, “Install the LILO boot loader on a hard disk.”

LILO installation target: /dev/md0: software RAID array

Another dialog occurs, titled “Configuring lilo.” Select Yes… or No. Was that helpful?

Another dialog:

It was detected that it's necessary to run /sbin/lilo in order to...

WARNING: This procedure will write data in your MBR...

Do you want to run /sbin/lilo now?

Select Yes and the install should complete.


References

https://help.ubuntu.com/9.04/serverguide/C/advanced-installation.html
http://tldp.org/HOWTO/Software-RAID-HOWTO.html
https://help.ubuntu.com/community/Installation/RAID1%2BLVM

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