Connect to the iSCSI targets by Open-iSCSI Initiator on Ubuntu Linux

About Linux Open-iSCSI Initiator The Linux Open-iSCSI Initiator is a built-in package in Ubuntu 8.04 LTS (or later). You can connect to an iSCSI volume at a shell prompt with just a few commands. More information about Ubuntu is available at http://www.ubuntu.com and for information and download location of Open-iSCSI, please visit: http://www.open-iscsi.org

Before you start Install the open-iscsi package. The package is also known as the Linux Open-iSCSI Initiator.

# sudo apt-get install open-iscsi

Now follow the steps below to connect to an iSCSI target (QNAP NAS) with Linux Open-iSCSI Initiator.

You may need to modify the iscsid.conf for CHAP logon information, such as node.session.auth.username & node.session.auth.password.

# vi /etc/iscsi/iscsid.conf

Save and close the file, then restart the open-iscsi service.

# /etc/init.d/open-iscsi restart

Discover the iSCSI targets on a specific host (the QNAP NAS in this example), for example, 10.8.12.31 with default port 3260.

# iscsiadm -m discovery -t sendtargets -p 10.8.12.31:3260

Check the available iSCSI node(s) to connect.

# iscsiadm -m node

** You can delete the node(s) you do not want to connect to when the service is on with the following command:

# iscsiadm -m node –op delete –targetname THE_TARGET_IQN

Restart open-iscsi to login all the available nodes.

# /etc/init.d/open-iscsi restart

You should be able to see the login message as below:

Login session [iface: default, target: iqn.2004-04.com:NAS:iSCSI.ForUbuntu.B9281B, portal: 10.8.12.31,3260] [ OK ]

Check the device status with dmesg.

# dmesg | tail

Enter the following command to create a partition, /dev/sdb is the device name.

# fdisk /dev/sdb

Format the partition.

# mkfs.ext3 /dev/sdb1

Mount the file system.

# mkdir /mnt/iscsi

# mount /dev/sdb1 /mnt/iscsi/

You can test the I/O speed using the following command.

# hdparm -tT /dev/sdb1

Below are some “iscsiadm” related commands.

Discover the targets on the host:

# iscsiadm -m discovery –type sendtargets –portal HOST_IP

Login a target:

# iscsiadm –m node –targetname THE_TARGET_IQN –login

Logout a target:

# iscsiadm –m node –targetname THE_TARGET_IQN –logout

Delete a Target:

# iscsiadm –m node –op delete –targetname THE_TARGET_IQN