Following the installation procedure, but with software raid support.
I. SOFTWARE RAID CONFIGURATION.Choose expert mode installation:
Once in the partition disks menu, select “Manual”:
Go to the free space of the “sda” disk:
Create a new partition:
Choose the maximum partition size:
Then select the type of partition, logical in our case:
Change partition characteristics for raid volume:
Validate the end of the configuration:
Do the same operations above for the “sdb” disk.Once the two raid volumes have been created, let's go to the software raid configuration:
Apply changes to disks:
Then create a multi-disk device:
Select “Raid1”:
Check the number of active devices, 2 in our case:
Leave the spare device count at 0:
Overview of active devices and selection thereof: (space to select)
Finish configuring volumes:
Finish partitioning and apply changes:
Appears a new Raid1 device:
Select free space to apply partition characteristics:
Apply the filesystem type, journaled ext4 in our example:
Select the partition mount point, root “/” in our case:
Finish setting the raid partition:
Finish partitioning and apply changes:

After applying the changes on the disks the installation of Zentyal continues
with software raid1 support.
Once the installation is complete, to verify the volumes, enter the command below
in a terminal:
We see a raid1 volume md0 belonging to disk sda partition sda5, same for
sdb5.
II. RAID MAINTENANCETo display the status of a raid1 volume enter the following command:sudo mdadm -D /dev/md0
Output of the above command:
To remove a bad volume: (* select the bad disk number)sudo mdadm --remove /dev/md0 /dev/sda*
To add a new volume:sudo mdadm --add /dev/md0 /dev/sda*
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