Configuring iSCSI ports
Overview of iSCSI operations
Internet SCSI (iSCSI) is a protocol for sending and receiving SCSI commands through an IP network. iSCSI transfers data in block units. An IP-SAN that uses an existing Ethernet can be constructed by using iSCSI. In a network for iSCSI, LUN Manager manages access paths between hosts and volumes for each port in your storage system.
LUN Manager provides the following features for managing iSCSI-connected volumes:
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Connecting multiple hosts to an iSCSI port
You can connect more than one host to a port on your storage system.
When setting up host connections, for each host you specify the settings for host mode, volume, and iSCSI target. Each host can access a volume simulating a dedicated port to the host even if that host shares the port with other hosts.
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Mapping volumes to hosts
You can map or assign volumes to the hosts on your network. You have complete flexibility to share or restrict volume access among the hosts.
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Network security
You can enable or disable CHAP (Challenge Handshake Authentication Protocol), a security protocol that requires users to enter a secret for access.
Network configuration for iSCSI
An iSCSI connection makes it possible to construct an IP-SAN by connecting many hosts and storage systems at a low cost. However, iSCSI greatly increases the I/O workload of the network and the storage system. When using iSCSI, it is very important that you configure the network so that the workload among the network, port, controller, and drive is properly distributed.
Even though the LAN switches and NICs are the same, there are some important differences when you use iSCSI, particularly regarding the LAN connection. You need to focus particular attention to the following:
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iSCSI consumes almost all of the available Ethernet bandwidth, unlike a conventional LAN connection. This can significantly degrade the performance of both the iSCSI traffic and the LAN. Therefore, it is very important that you separate the iSCSI IP-SAN and the office LAN.
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Host I/O load will affect the iSCSI response time. In general, the greater the I/O traffic is, the lower the iSCSI performance.
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You need to have a failover path between host and iSCSI, so that you can update the firmware without stopping the system.
The following figure shows LU paths configuration in a Fibre Channel environment. The figure shows the iSCSI target 00 associated with three logical volumes (00:00:00, 00:00:01, and 00:00:02). LU paths are defined between the two hosts in the iSCSI target 00 and the three logical volumes.

You can define paths between a single server host and multiple LUs. The figure shows that each of the two hosts in the iSCSI target 00 can access the three LUs.
You can also define paths between multiple server hosts and a single LU. The figure shows that the LU identified by the LDKC:CU:LDEV number 00:00:00 is accessible from the two hosts that belong to the iSCSI target 00.
Multi VLAN operations with iSCSI virtual port mode
Multi VLAN operations are supported with the iSCSI virtual port mode. The iSCSI virtual port mode enables you to add up to 16 virtual ports to a single physical iSCSI port. Virtual ports are used to access the storage system using multiple segments that are divided by VLAN, enabling efficient use of ports and network resources.
You can perform the following multi VLAN operations using Command Control Interface. For details about enabling and disabling iSCSI virtual ports, see the Command Control Interface User and Reference Guide.
- Enabling and disabling the iSCSI virtual port mode
- Adding and deleting virtual ports

- The iSNS function cannot be used when the iSCSI virtual port mode is enabled.
- If the iSCSI virtual port mode is enabled, the port information when the virtual port mode is disabled is taken over to the iSCSI virtual port ID (0). If iSCSI port IDs from 1 to 15 are added, specify IPv4 or IPv6.
- If an IPv6 address is used on a virtual port, multiple virtual ports cannot be used in the same network.
- When the setting for the virtual port mode is changed, Link Down/Link Up (temporary disconnecting) occurs on the target iSCSI port. Because this operation temporarily disconnects the iSCSI port (Link Down/Link Up), you should change the mode only when the I/O loads are low.
Editing iSCSI port settings
Use this procedure to edit the iSCSI port settings.
When the iSCSI virtual port mode is enabled for a port, the following items cannot be set using Device Manager - Storage Navigator:
- IPv4 Settings
- IPv6 Mode
- IPv6 Settings
- TCP Port Number
- Selective ACK
- Delayed ACK
- Maximum Window Size
- Ethernet MTU Size
- Keep Alive Timer
- VLAN Tagging Mode
- iSNS Server
To edit iSCSI ports for which the virtual port mode is enabled, use Command Control Interface. For details, see the Command Control Interface documentation.
Before you begin
- The Storage Administrator (System Resource Management and Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets, and select the Ports tab.
Select the desired port, and click Edit Ports.
Select the check box to change the option and specify values. Items that can be changed are as follows:
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IPv4 Settings: Specifies IP Address, Subnet Mask, or Default Gateway.
- IPv6 Mode: Specifies enable or disable of this mode.
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IPv6 Settings: Specifies Link Local Address, Global Address, Global Address 2, or Default Gateway if IPv6 Mode is selected to Enable.
- Port Security: Specifies enable or disable.
- Port Speed: Specifies the data transfer speed.
- TCP Port Number: Specifies the TCP port number.
- Selective ACK: Specifies enable or disable.
- Delayed ACK: Specifies enable or disable.
- Maximum Window Size: Specifies the size of the maximum window.
- Ethernet MTU Size: Specifies the MTU size.
- Keep Alive Timer: Specifies the keep alive timer.
- VLAN Tagging Mode: Specifies enable or disable.
- iSNS Server: Specifies enable or disable. If this option is selected to Enable, specify IP Address or TCP Port Number.
- CHAP User Name: Specifies the CHAP user name.
- Secret and Re-enter Secret: Specifies the secret which is used for host authentication.
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Click Finish. A message appears, confirming whether to switch the LUN security. Clicking OK opens the Confirm window.
In the Confirm window, confirm the settings, in Task Name type a unique name for this task or accept the default, then click Apply. If Go to tasks window for status is checked, the Tasks window opens.
Configuring CHAP users
Adding CHAP users
Before you begin
- The Storage Administrator (Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets.
Select the iSCSI target to register CHAP users.
Display the Add CHAP Users window by performing one of the following:
- Click More Actions, select Add CHAP Users.
- From the Actions menu, select Ports/Host Groups/iSCSI, Authentication, then Add CHAP Users.
In the Available CHAP Users table, select the CHAP user row. Click Add. The selected CHAP user is registered in the Selected CHAP Users table. If the CHAP user does not exist, perform the following steps to register a new CHAP user:
Click Add New CHAP User under the Available CHAP Users table. The Add New CHAP User dialog box opens.
Specify User Name and Secret.
Click OK to close the Add New CHAP User dialog box.
Click Finish to display the Confirm window.
Confirm the settings and enter the task name in the Task Name box. A task name can consist of up to 32 ASCII characters (letters, numerals, and symbols). Task names are case-sensitive. (date) - (task name) is input by default.
Click Apply in the Confirm window. If the Go to tasks window for status check box is selected, the Tasks window appears.
Editing CHAP users
Before you begin
- The Storage Administrator (Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets.
Select the CHAP users.
Display the Edit CHAP Users window by performing one of the following:
- Click Edit CHAP Users.
- From the Actions menu, select Ports/Host Groups/iSCSI, Authentication, then Edit CHAP Users.
Specify User Name and Secret.
Click Finish to display the Confirm window.
Confirm the settings and enter the task name in the Task Name box. A task name can consist of up to 32 ASCII characters (letters, numerals, and symbols). Task names are case-sensitive. (date) - (task name) is input by default.
Click Apply in the Confirm window. If the Go to tasks window for status check box is selected, the Tasks window appears.
Removing CHAP users
Before you begin
- The Storage Administrator (Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets.
Select the CHAP users.
Display the Remove CHAP Users window by performing one of the following:
- Click Remove CHAP Users.
- From the Actions menu, select Ports/Host Groups/iSCSI, Authentication, then Remove CHAP Users.
Specify User Name and Secret.
Click Finish to display the Remove CHAP Users window.
Confirm the settings and enter the task name in the Task Name box. A task name can consist of up to 32 ASCII characters (letters, numerals, and symbols). Task names are case-sensitive. (date) - (task name) is input by default.
Click Apply in the Confirm window. If the Go to tasks window for status check box is selected, the Tasks window appears.
Removing target CHAP users
Before you begin
- The Storage Administrator (Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets.
Select the iSCSI target.
Display the Remove Target CHAP Users window by performing one of the following:
- Click .
- From the Actions menu, select Ports/Host Groups/iSCSI, Authentication, then Remove Target CHAP Users.
Confirm the settings and enter the task name in the Task Name box. A task name can consist of up to 32 ASCII characters (letters, numerals, and symbols). Task names are case-sensitive. (date) - (task name) is input by default.
Click Apply in the Confirm window. If the Go to tasks window for status check box is selected, the Tasks window appears.
Removing port CHAP users
Before you begin
- The Storage Administrator (Provisioning) role is required to perform this task.
- The Security Administrator (View and Modify) role is required to perform this task.
Procedure
Click Storage Systems, and then expand the Storage Systems tree.
Click Ports/Host Groups/iSCSI Targets.
Select the port CHAP user port name to be removed.
Display the Remove Port CHAP Users window by performing one of the following:
- Click Remove Port CHAP Users.
- From the Actions menu, select Ports/Host Groups, iSCSI, Authentication, then Remove Port CHAP Users.
Confirm the settings and enter the task name in the Task Name box.
A task name can consist of up to 32 ASCII characters (letters, numerals, and symbols). Task names are case-sensitive. (date) - (task name) is input by default.Click Apply in the Confirm window.
If the Go to tasks window for status check box is selected, the Tasks window appears.