Mount and use a volume

How to mount and use a Block Storage volume

Reviewed on 08 June 2023 • Published on 29 November 2019

To use a storage device on Linux it must be mounted (attached) to the operating system. Once it is mounted, a filesystem can be created on the device to store data. Similarly, to remove the device securely from the operating system, you should unmount it properly.

This document explains how to mount an additional block volume to your Instance. Note that the root volume of the Instance is mounted for you at the time of Instance creation, this how-to concerns additional block volumes only.

Security & Identity (IAM):

You may need certain IAM permissions to carry out some actions described on this page. This means:

you are the Owner of the Scaleway Organization in which the actions will be carried out, or
you are an IAM user of the Organization, with a policy granting you the necessary permission sets

Requirements:

You have an account and are logged into the Scaleway console
You have configured your SSH key
You have an Instance with an attached additional Block Storage volume

How to verify device availability

Connect to your Instance with ssh.
```
ssh root@<your_instance_ip>
```
Use the lsblk command to make sure your block volume is available:
```
lsblk
```

You should see an output like the following. You can see your block volume named sda with the chosen storage size.

root@scw-festive-agnesi:~# lsblk
NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda       8:0    0 23.3G  0 disk
vda     252:0    0 18.6G  0 disk
├─vda1  252:1    0 18.5G  0 part /
└─vda15 252:15   0  100M  0 part /boot/efi

Note:

The Scaleway ecosystem uses GiB to define storage sizes and not GB as the default on linux.

How to format the Block Volume

Create a file system with the following command. This command uses the ext4 filesystem, though you can choose another if you prefer.
```
mkfs.ext4 /dev/sda
```
Make sure your file system is correctly created by running the lsblk -f command.
```
lsblk -f
```

You should see an output like the following. Check that the FSTYPE field matches ext4 for your Block volume.

root@scw-festive-agnesi:~# lsblk -f
NAME    FSTYPE LABEL UUID                                 MOUNTPOINT
sda     ext4         925c2c17-ca8c-493a-a9cd-b475d87fd276
vda
├─vda1  ext4   root  8509fe04-d91c-410a-9087-c5d34537d3ae /
└─vda15 vfat         B3E7-7040                            /boot/efi

How to mount the Block Volume

Once your file system is created, you need to mount it.

Create the mount point. In this tutorial, we choose /mnt/block-volume.
```
mkdir /mnt/block-volume
```

Mount the volume. We recommend you use the defaults option, as in the command below.

mount -o defaults /dev/sda /mnt/block-volume

    **defaults**
          Use  the  default  options: **rw**, **suid**, **dev**,
          **exec**, **auto**, **nouser**, and **async**.

If you want to see all available options, you can run man mount on your Instance.

Make sure your file system is properly mounted by running the lsblk command.

lsblk

You should see an output like the following. Check the MOUNTPOINT field.

root@scw-festive-agnesi:~# lsblk
NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda       8:0    0 23.3G  0 disk /mnt/block-volume
vda     252:0    0 18.6G  0 disk
├─vda1  252:1    0 18.5G  0 part /
└─vda15 252:15   0  100M  0 part /boot/efi

How to use fstab for Persistent Mounting

With the current configuration, the block device will not be mounted automatically upon reboot. Use the fstab file to make sure the reboot does not impact your file system.

Add this line to the /etc/fstab file of your Instance:

echo "UUID=$(blkid --output value /dev/sda | head -n1) /mnt/block-volume ext4 defaults 0 0" >> /etc/fstab

How to transfer data from your local machine to the remote block volume

You may wish to transfer files from your local machine to your Instance’s remote block volume. This can be simply achieved with rsync, a tool for efficiently transferring and copying files. The rsync utility is preinstalled on most Linux distributions and macOS.

Check that rsync is installed on your local machine with the following command:

rsync --version

You should see an output similar to the following:

rsync  version 3.1.3  protocol version 31
Copyright (C) 1996-2018 by Andrew Tridgell, Wayne Davison, and others.
Web site: http://rsync.samba.org/
Capabilities:
    64-bit files, 64-bit inums, 64-bit timestamps, 64-bit long ints,
    socketpairs, hardlinks, symlinks, IPv6, batchfiles, inplace,
    append, ACLs, xattrs, iconv, symtimes, prealloc
rsync comes with ABSOLUTELY NO WARRANTY.  This is free software, and you
are welcome to redistribute it under certain conditions.  See the GNU
General Public Licence for details.

Tip:

If you get a command not found output (or similar), you need to install rsync. On Linux Ubuntu and Debian systems, you can do this with the APT package tool using the command sudo apt install rsync. For Linux CentOS/ Fedora, use the YUM package manager: sudo yum install rsync. On Mac OSX with the Homebrew package manager, use brew install rsync.

On your local machine, use nano to create a file called hello-world.txt:
```
nano hello-world.txt
```
Enter the text Hello World!, then save and exit the file.
Enter the following command to transfer the file to your Instance’s mounted block volume. Ensure that you use your own Instance’s IP address:
```
rsync -a hello-world-2.txt root@<your.IP.address.here>:/mnt/block-volume
```

The file is now transferred. You can connect to your Instance again, and use the command cd /mnt/block-volume ; ls to check that the file appears in the directory.