Software iSCSI Storage

A Software iSCSI SR uses a shared Logical Volume Manager (LVM) on a SAN attached LUN over iSCSI. iSCSI is supported using the open-iSCSI software iSCSI initiator or by using a supported iSCSI Host Bus Adapter (HBA).

Note that dynamic multipathing support is available for iSCSI storage repositories. By default, multipathing uses round robin mode load balancing, so both routes will have active traffic on them during normal operation. You enable and disable storage multipathing in XenCenter via the Multipathing tab on the server’s Properties dialog; see Storage Multipathing.

To create a software iSCSI SR

Note: Before performing the following steps, ensure the iSCSI Initiator IQN is set appropriately for all hosts in the pool. For more information, see Changing Server Properties.

1. Open the New Storage Repository wizard: click New Storage on the toolbar. Alternatively:
   • On the Storage tab for the selected pool or server, click New SR.
   • On the Storage menu, click New SR.
   • In the Resources pane, select a server or pool then right-click and click New SR on the shortcut menu.
2. Select Software iSCSI as the physical storage type, then click Next.
3. On the Name page, enter the name of the new SR. By default, a description of the SR will be generated automatically by the wizard, including a summary of the configuration options you select as you progress through the wizard. To enter your own description, clear the Auto-generate description check box and type in the Description box. Click Next to continue.
4. On the Location page, specify the iSCSI target details:
   • Target Host: The IP address or DNS name of the iSCSI target.

   • Use CHAP:

     If the iSCSI target is configured to used CHAP authentication, select the Use CHAP check box and fill in the details:

     • CHAP User: the CHAP authentication username credential that should be applied when connecting to the target.
     • CHAP Secret: the CHAP authentication password credential that should be applied when connecting to the target.

   • Target IQN: To specify the iSCSI target IQN, click the Discover IQNs button and then choose an IQN from the Target IQN list.

     Important: The iSCSI target and all servers in the pool must not have the same IQN set. It is imperative that every iSCSI target and initiator have a unique IQN. If a non-unique IQN identifier is used, data corruption can occur and/or access to the target may be denied.

   • Target LUN: To specify the LUN on which the storage repository will be created, click the Discover LUNs button and then choose a LUN from the Target LUN list.

     Each individual iSCSI storage repository must be contained entirely on a single LUN (Logical Unit Number), and may not span more than one LUN. If the LUN already contains an SR, you can either use the existing SR or you can replace the existing SR with a new one, destroying any data present on the disk.

5. Click Finish to complete the new SR configuration and close the wizard.