Oracle Cloud Infrastructure Documentation

Connecting to Volumes With Consistent Device Paths

Oracle Cloud Infrastructure supports consistent device paths for block volumes attached to compatible Linux-based instances launched from Oracle-provided platform images. When you attach a block volume to an instance you can optionally select a device path that will remain consistent between instance reboots so you can use this path when you refer to the volume to perform tasks such as:

  • Creating partitions.

  • Creating file systems.

  • Mounting file systems.

  • Specifying options in in the /etc/fstab file to ensure volumes are mounted properly when automatically mounting volumes on instance boot.

When you use consistent device paths on compatible Linux-based instances the boot volume's device path is:

/dev/oracleoci/oraclevda

Tip

For instances that support consistent device paths, while it is optional, we recommend that you select a device path when attaching a data volume. If you do not specify a device path for attached block volumes, there is no guarantee that the boot volume device path will be: /dev/oracleoci/oraclevda.

Images that Support Consistent Device Paths

Consistent device paths are supported on instances created from Oracle-provided Linux-based images released in November 2018 and later, with the exception of instances launched prior to January 11th, 2019, see Device path option not available for instances launched before January 11th, 2019.

The following Linux-based images do not support consistent device paths:

  • Oracle-provided Linux-based images released prior to November 2018

  • Custom images

  • Partner images

This feature does not apply to Windows-based images.

You can do a simple test to check whether your instance supports consistent device paths.

To verify consistent device path support on your instance

Device Paths in the Console

When you attach a block volume to an instance that supports consistent device paths, you will see the DEVICE PATH dropdown in the Attach Block Volume dialog as shown in the following screen shot:

Screenshot showing device paths field in Attach Block Volume dialog

This optional selection is covered in step 8 of Attaching a Volume. If you selected a device path you will see your selection in the Device Path field for the volume in the Attached Block Volumes list for the instance, as shown in the following screen shot.

Screenshot showing device path field for an attached block volume

If you did not specify a device path, this field will be blank.

Device Paths on the Instance

Following are sample commands for performing various configuration tasks on the attached volume, showing first the command for volumes not using consistent device paths and then the command for volumes where you have specified a device path.

Creating a partition with fdisk
Creating an ext3 file system
Updating the /etc/fstab file
Mounting the file system