Configuring tcp/ip services, Configuring vlans, Enabling ethernet jumbo frames – HP EVA Array iSCSI Connectivity Option User Manual

Page 90: Configuring target discovery

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Configuring TCP/IP services

Before you start the iSCSI Initiator, TCP/IP must be properly configured and enabled. The initiator will

only function with the TCP/IP stack provided by HP TCP/IP Services for OpenVMS. Only the basic

TCP/IP core functionality needs to be configured. Note that particular attention should be paid to the

system’s hostname, which is a defining element in the iSCSI Initiator name (a unique name assigned

to each host running the iSCSI Initiator software). TCP/IP must be running and the hostname must be

set before the iSCSI Initiator is loaded.

Configuring VLANs

While not mandatory, if the initiator will be operating on a shared network (a network not dedicated

solely to storage), it is suggested that storage traffic be isolated to a dedicated Virtual LAN (VLAN).

The VLAN will logically isolate storage traffic into its own subnet.
In order to configure and use a VLAN, the hosts, network switches, and targets must all support IEEE

802.1Q. For information on configuring VLANs on the OpenVMS hosts, see the HP OpenVMS Version

8.3 New Features and Documentation Overview and the HP OpenVMS System Management Utilities

Reference Manual. For information on configuring VLANs on the network switches, see your switch

manufacturer’s documentation. VLAN configuration on the mpx100/100b targets will be performed

during their installation and configuration (see section

Installation and maintenance

, page 55.)

Enabling Ethernet jumbo frames

If Ethernet jumbo frames are to be used for iSCSI traffic, they must be enabled on the initiators (OpenVMS

hosts), network switches, and targets. To enable jumbo frames system-wide on an OpenVMS host node

using the LAN_FLAGS system parameter, see the HP OpenVMS System Management Utilities Reference

Manual. To enable jumbo frames on a per-device basis, see the HP OpenVMS System Manager’s

Manual.

Configuring target discovery

The OpenVMS Software-Based iSCSI Initiator supports two target discovery mechanisms – manual and

iSNS. At least one of these methods must be configured on each iSCSI-enabled OpenVMS host:

Manual target discovery

With manual target discovery, the initiator is supplied with a list of IP addresses for each iSCSI target

port. Each mpx100 has two iSCSI target ports. (The management port is not an iSCSI target port.) An

initiator using this discovery method will periodically poll each target port in its manual discovery list

to gather a list of accessible storage devices.

1.

To create a manual target list, copy the file

SYS$COMMON:[SYSMGR]ISCSI$MANUAL_TARGETS.TEMPLATE

to

SYS$COMMON:[SYSMGR]ISCSI$MANUAL_TARGETS.DAT

The directory SYS$SPECIFIC:[SYSMGR] can be used if the file is to be node-specific rather

than cluster-wide.

2.

Edit the new file and add a list of the IP names or addresses of the iSCSI target ports that should

be probed for available storage devices. The header included in this file defines the proper

format for these addresses. The manual target list is automatically loaded when the iSCSI Initiator

is started. By default, changes to this file will not take effect until the system is rebooted or until

the initiator is stopped and restarted.

3.

To manually force the initiator to recognize additions to the manual target list while the initiator is

running, issue the following command:

$ mcr iscsi$control_program manual

Target ports that have been added to this file since the initiator was started will be added to the

list of target ports that are periodically scanned by the initiator. Note that target ports that have

90

Setting up the iSCSI Initiator and storage

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