Mount a volume on Linux

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After you attach a volume to a Linux node, it appears as a block device. To use it, you format it with a file system (if it is empty) and mount it at a directory. Once mounted, everything you write to that directory is stored on the volume. The examples assume the volume shows up as /dev/vdb and your node’s own root disk is /dev/vda1; your device names can differ, so check them first.

Before you begin

A volume attached to the node. See Attach a volume.
Access to the node over SSH.

Find the volume’s device name

On the node, list the block devices:

lsblk

The attached volume is the unmounted device, for example /dev/vdb. Check its device name before doing anything else.

Check whether the volume needs formatting

An empty volume has no file system and must be formatted; a volume created from a snapshot often already has one. Check which you have:

sudo file -s /dev/vdb

If it prints data, the volume has no file system. If it prints a type such as XFS or ext4, it is already formatted, skip the formatting step and do not format it again, or you erase its data.

Format the volume

An empty volume needs a file system. This example uses XFS; ext4 also works if you prefer it.

sudo mkfs -t xfs /dev/vdb

Formatting erases all data on the volume. Run it only on an empty volume, never on one created from a snapshot or one that already holds data. If the command is not found, install the XFS utilities: sudo yum install -y xfsprogs, or on Ubuntu sudo apt install -y xfsprogs.

Mount the volume

Create a directory to mount it at, for example /data:
```
sudo mkdir /data
```
Mount the volume to that directory:
```
sudo mount /dev/vdb /data
```
Confirm the mount:
```
df -h
```

You can read and write to /data now, and the volume stores it.

Keep the mount across a reboot

To keep the mount across reboots, add it to /etc/fstab by the device’s UUID.

Find the UUID:
```
sudo blkid /dev/vdb
```
The output shows a line like UUID="e7c5b2f2-..." TYPE="xfs". Copy the UUID value.
Edit /etc/fstab:
```
sudo nano /etc/fstab
```

Add a line at the end, using your own UUID and mount point:

UUID=e7c5b2f2-8b2a-4e13-b9a9-bb3f122a91f1   /data   xfs   defaults,nofail   0   2

Apply the configuration and check for errors:
```
sudo mount -a
```

If mount -a prints no errors, the setup is correct. Reboot the node and run df -h again to confirm /data mounts automatically.

The volume is mounted and stays mounted across reboots. When you later detach it, unmount it and remove its /etc/fstab line first; see Detach a volume. If it will not mount, see Troubleshooting Volumes.