Working with Multipath-Enabled iSCSI-Attached Volumes

A device path is required for multipath-enabled volume attachments. When attaching a volume configured for the Ultra High Performance level, using the iSCSI attachment type, the Attach button is not enabled until you select a device path. For more information about device paths, see Connecting to Volumes With Consistent Device Paths.

If you change the performance of an attached volume to the Ultra High Performance level and it was attached without a device path, it will not be multipath-enabled. This means that it will not be capable of the Ultra High Performance level numbers, until you specify a device path. You need to detach the volume, and then specify a device path when you reattach it to the instance.

To determine the friendly name for the multipath-enabled attached volume, connect to the instance and run the following command:

ls -l <Consistent_Device_Path>

If you have the friendly name for the device, run the following command to retrieve the device path name

sudo multipath -ll <Friendly_Name>

Use fdisk to partition the multipath-enabled volume, and use the n option to specify that it's a new partition.

fdisk <Friendly_Name

Use the p option to make it the primary partition.

Run the following command to list the partitions:

lsblk

Run the following command to create the file system:

mkfs.ext4 <Friendly_Name>

Run the following commands to create a directory and mount the partition on the mount point:

mkdir /data 

mount <Friendly_Name> /data

On Linux instances, if you want to automatically mount volumes on instance boot, you need to set some specific options in the /etc/fstab file, or the instance may fail to launch.

blkid

<Volume_UUID> /data ext4 defaults,_netdev,noatime 0 2

mount -a