Longhorn supports iSCSI target frontend mode. You can connect to it through any iSCSI client, including open-iscsi, and virtual machine hypervisor like KVM, as long as it’s in the same network as the Longhorn system.

The Longhorn CSI driver doesn’t support iSCSI mode.

To start a volume with the iSCSI target frontend mode, select iSCSI as the frontend when creating the volume.

After the volume has been attached, you will see something like the following in the endpoint field:

iscsi://10.42.0.21:3260/iqn.2014-09.com.rancher:testvolume/1

In this example,

• The IP and port is 10.42.0.21:3260.
• The target name is iqn.2014-09.com.rancher:testvolume.
• The volume name is testvolume.
• The LUN number is 1. Longhorn always uses LUN 1.

The above information can be used to connect to the iSCSI target provided by Longhorn using an iSCSI client.