If you have two hard drives, and want to mirror the data on your drives, then the RAID configuration that would suit your needs is RAID 1.

You can type

lsmod |grep network/eth/wlan

if don have you must install network driver

The only initial downside of using software RAID1 is that it is the partitions that are mirrored, not the drives themselves. When the install process configures Grub to boot the server, it will only do it on the first drive. If that was to fail and the server restarted, any attempt to boot from the second drive will fail. Use the following (although the first three lines are normally optional) to configure both drives correctly:

grub>device (hd0) /dev/sda

grub>root (hd0,0)

grub>setup (hd0)

grub>device (hd0) /dev/sdb

grub>root (hd0,0)

grub>setup (hd0)

The "device (hd0) /dev/sdb" is important: It tells grub to treat the drive as if it was sda when configuring it, not sdb. When it reboots, it will essentially become sda and therefore grub will see it as the first disk; if its looking around for sdb it won't find the /boot partition and fail to boot.

Hi,

If you have only two disks and want redundancy then the you want to use RAID 1. RAID 1 is often referred to as mirroring since each disk in the array is a mirror of the other and contains the same data. What gets written to one is written to the other so in the event that one of the disk fails no data is lost.

You may have a hardware RAID controller in your server. If not Linux provides a software RAID solution and you can configure this when you reach the disk partitioning stage of your Ubuntu install. You can find more information on setting up software RAID here.

https://help.ubuntu.com/community/Installation/SoftwareRAID

Correct, when the drive fails OS will continue to run till you replace the drive, unless the other drive fails before you replace the failed one.

If the server support hot swappable drives then you wont even need to turn it off to replace the failed one

Thanks. Would this mean that if one drive failed I wouldn't need access to the Server (unless I was to replace the failed drive) but it would keep running automatically ?