How to attach a volume to VM less than 2TB on Linux on Eumetsat Elasticity

In this tutorial, you will create a volume which is smaller than 2 TB. Then, you will attach it to a VM and format it in the appropriate way.

Note

If you want to create and attach a volume that has more than 2 TB of storage, you will need to use different software for its formatting. If this is the case, please visit the following article instead: How to attach a volume to VM more than 2TB on Linux on Eumetsat Elasticity.

What We Are Going To Cover

  • Creating a new volume

  • Attaching the new volume to a VM

  • Formatting and mounting of the new volume

Prerequisites

No. 1 Hosting

You need a Eumetsat Elasticity hosting account with Horizon interface https://horizon.cloudferro.com/auth/login/?next=/.

No. 2 Linux VM running on the Eumetsat Elasticity cloud

Instructions for creating and accessing a Linux VM using default images can be found here:

How to create a Linux VM and access it from Linux command line on Eumetsat Elasticity

or here:

How to create a Linux VM and access it from Windows desktop on Eumetsat Elasticity.

The instructions included in this article are designed for Ubuntu 22.04 LTS.

No. 3 Basic knowledge of the Linux terminal

You will need basic knowledge of the Linux command line.

No. 4 SSH access to the VM

How to connect to your virtual machine via SSH in Linux on Eumetsat Elasticity.

Step 1: Create a Volume

Login to the Horizon panel available at https://horizon.cloudferro.com/auth/login/?next=/.

Go to the section Volumes -> Volumes:

../_images/volume-less-01_creodias.png

Click Create Volume.

The following window should appear:

../_images/volume-less-02_creodias.png

In it provide the Volume Name of your choice.

Choose the Type of your volume - SSD or HDD.

Enter the size of your volume in gigabytes.

When you’re done, click Create Volume.

You should now see the volume you just created. In our case it is called volume-small:

../_images/volume-less-03_creodias.png

Step 2: Attach the Volume to VM

Now that you have created your volume, you can use it as storage for one of your VMs. To do that, attach the volume to a VM.

In the Actions menu for that volume select the option Manage Attachments:

../_images/volume-less-04_creodias.png

You should now see the following window:

../_images/volume-less-05_creodias.png

Select the virtual machine to which the volume should be attached:

../_images/volume-less-06_creodias.png

Click Attach Volume.

Your volume should now be attached to the VM:

../_images/volume-less-07_creodias.png

Step 3: Partition the Volume

It is time to access your virtual machine to prepare the volume for data storage.

Connect to your virtual machine using SSH or the web console.

Execute the following command to make sure that the volume has been attached:

lsblk

You should see the output similar to this:

../_images/volume-less-08_creodias.png

In this example, the attached volume that was previously called volume-small is represented by the device file sdb. Its size is 100 GB. Memorize the name of the device file representing the drive you attached or write it somewhere down - it will be needed later during starting fdisk.

In order to be able to use the volume as storage, you will need to use fdisk to create a partition table.

Start fdisk (replace sdb with the name of the device file provided to you previously by the lsblk command):

sudo fdisk /dev/sdb

You should now see the following prompt:

Command (m for help):

Answer with n and press Enter. A series of prompts similar to the ones below will appear on screen - keep pressing Enter on your keyboard to accept the default values.

Partition type
p   primary (0 primary, 0 extended, 4 free)
e   extended (container for logical partitions)
Select (default p):

Using default response p.
Partition number (1-4, default 1):
First sector (2048-209715199, default 2048):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-209715199, default 209715199):

You should now see the confirmation similar to this:

Created a new partition 1 of type 'Linux' and of size 100 GiB.

After it you will see the following prompt again:

Command (m for help):

This time, answer with w. You will see the following message:

The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

Execute the following command again to confirm that the partition was created successfully:

lsblk

The device file of the new partition should have the same name as the device file of the drive followed by the 1 digit. In this case, it will be sdb1. Memorize or write it somewhere down - it will be needed later during creation of the file system.

../_images/volume-less-09_creodias.png

Step 5: Create the File System

In order to save data on this volume, create ext4 filesystem on it. ext4 is arguably the most popular filesystem on Linux distributions.

It can be created by executing the following command:

sudo mkfs.ext4 /dev/sdb1

Replace sdb1 with the name of the device file of the partition provided to you previously by the lsblk command.

This process should take less than a minute.

Step 6: Create the mount point

You need to specify the location in the directory structure from which you will access the data stored on that volume. In Linux it is typically done in the /etc/fstab config file.

Below are the instructions for the nano text editor. If you prefer to use different software, please modify them accordingly.

Install nano if you haven’t already:

sudo apt install nano

Open the /etc/fstab file using nano:

sudo nano /etc/fstab

Add the below line to the end of that file. Remember to replace sdb1 with the name of the device file of your partition (it was provided to you previously be the lsblk command) and /my_volume with the directory in which you want to mount it - the mounting point.

/dev/sdb1 /my_volume ext4 defaults 0 1
../_images/volume-less-10_creodias.png

To save that file in nano, use the following combination of keys: CTRL+X, Y, Enter.

Warning

Unless you know what you’re doing, you should not modify the lines which you already found in the /etc/fstab file. This file contains important information. Some or all of it might be required for the startup of the operating system.

Next, create a new or use an existing directory to use as your mounting point. If you need to create it anew, the command would be:

sudo mkdir /my_volume

Mount the volume to your system (replace /my_volume with your mountpoint):

sudo mount /my_volume

To check whether it was successfully mounted, execute:

df -h

The output should look like this:

../_images/volume-less-11_creodias.png

During the next boot of your virtual machine, the volume should be mounted automatically.

What To Do Next

You have successfully created a volume and prepared it for use on a Linux virtual machine.

You can now copy files to your new volume. If you want to move the data, attach the volume to a different machine.