Management changes for iSCSI in Data ONTAP 7.1

Administrative model changes

The overall administrative model for iSCSI is changed in Data ONTAP 7.1. These changes are necessary to support new iSCSI target functionality. The new iSCSI functions are:

Multi-connection sessions. Requires the ability to assign network interfaces to specific target portal groups. Sessions are no longer tied to adapters. Interfaces are managed by the standard networking commands (ifconfig, ifstat, vlan, and vif).
Target alias. Adds the ability to assign an alternate name to identify the storage system.
Error recovery level greater than zero. No administration needed. Requires an initiator that supports this function and has been qualified by NetApp.
Virtual interfaces (vifs) and VLAN-tagged interfaces are managed by the iSCSI command directly. You no longer enable and disable iSCSI for a virtual interface using the iswt command on the underlying physical interfaces.

Command line changes

The iscsi and iswt commands are changed as follows. See the man pages or the Data ONTAP 7.1 Commands: Manual Page Reference for the complete command syntax and options.

iswt interface replaced by iscsi interface
iswt session show replaced by iscsi session show
iswt connection show replaced by iscsi connection show
iscsi show initiator replaced by iscsi initiator show
iscsi config removed
iscsi show adapter removed
iscsi alias added
iscsi tpgroup added
iscsi portal show added
iscsi stats modified to report statistics for the entire storage system instead of for an individual adapter

FilerView changes

The FilerView LUN pages are changed as follows. See the FilerView help for information on specific fields and pages.

LUNs > iSCSI > Report page displays additional information
LUNs > iSCSI > Adapters page removed
LUNs > iSCSI > Initiator Security page renamed LUNs > iSCSI > Manage Initiator Security
LUNs > iSCSI > Manage Names page added
LUNs > iSCSI > Portal Addresses page added
LUNs > iSCSI > Manage Interfaces page added
LUNs > iSCSI > Initiators page added
LUNs > iSCSI > iSNS page renamed Manage iSNS

Enabling multi-connection sessions

By default, Data ONTAP 7.1 is configured to use a single TCP/IP connection for each iSCSI session. If you are using an initiator that has been qualified for multi-connection sessions, you can specify the maximum number of connections allowed for each session on the storage system.

Check the NetApp iSCSI support matrix to verify if your initiator has been qualified for multi-connection sessions. The matrix is available at
http://now.netapp.com/NOW/knowledge/docs/san/fcp_iscsi_config/
iscsi_support_matrix.shtml

The iscsi.max_connections_per_session option specifies the number of connections per session allowed by the storage system. You can specify between 1 and 16 connections, or you can accept the default value.

Note that this option specifies the maximum number of connections per session supported by the storage system. The initiator and storage system negotiate the actual number allowed for a session when the session is created; this is the smaller of the initiator's maximum and the storage system's maximum. The number of connection actually used also depends on how many connections the initiator establishes.

To view or change the setting of the iscsi.max_connections_per_session option, complete the following steps:

Step	Action
1	Verify the current option setting by entering the following command on the system console: options iscsi.max_connections_per_session Result The current setting is displayed.
2	If needed, change the number of connections allowed by entering the following command: options iscsi.max_connections_per_session [connections \| use_system_default] connections is the maximum number of connections allowed for each session, from 1 to 16. `use_system_default` equals 1 for Data ONTAP 7.1. The meaning of this default may change in later releases.

Step

Action

Verify the current option setting by entering the following command on the system console:

options iscsi.max_connections_per_session

Result

The current setting is displayed.

If needed, change the number of connections allowed by entering the following command:

options iscsi.max_connections_per_session

     [connections | use_system_default]

connections is the maximum number of connections allowed for each session, from 1 to 16.

use_system_default equals 1 for Data ONTAP 7.1. The meaning of this default may change in later releases.

Enabling error recovery levels 1 and 2

By default, Data ONTAP 7.1 is configured to use only error recovery level 0 for iSCSI sessions. If you are using an initiator that has been qualified for error recovery levels 1 or 2, you can specify the maximum error recovery level allowed by the storage system.

Check the NetApp iSCSI support matrix to verify if your initiator has been qualified for error recovery levels greater than 0. The matrix is available at
http://now.netapp.com/NOW/knowledge/docs/san/fcp_iscsi_config/
iscsi_support_matrix.shtml

There may be a minor performance reduction for sessions running error recovery level 1 or 2.

The iscsi.max_error_recovery_level option specifies the maximum error recovery level allowed by the storage system. You can specify 0, 1, or 2, or you can accept the default value.

Note that this option specifies the maximum error recovery level supported by the storage system. The initiator and storage system negotiate the actual error recovery level used for a session when the session is created; this is the smaller of the initiator's maximum and the storage system's maximum.

To view or change the setting of the iscsi.max_error_recovery_level option, complete the following steps:

Step	Action
1	Verify the current option setting by entering the following command on the system console: options iscsi.max_error_recovery_level Result The current setting is displayed.
2	If needed, change the error recovery levels allowed by entering the following command: options iscsi.max_error_recovery_level [level \| use_system_default] level is the maximum error recovery level allowed, 0, 1, or 2. `use_system_default` equals 0 for Data ONTAP 7.1. The meaning of this default may change in later releases.

Step

Action

Verify the current option setting by entering the following command on the system console:

options iscsi.max_error_recovery_level

Result

The current setting is displayed.

If needed, change the error recovery levels allowed by entering the following command:

options iscsi.max_error_recovery_level

     [level | use_system_default]

level is the maximum error recovery level allowed, 0, 1, or 2.

use_system_default equals 0 for Data ONTAP 7.1. The meaning of this default may change in later releases.