Implement iSCSI on AIX

 

Learn how to implement the Internet small computer system interface (iSCSI) on Aix ). This step-by-step process describes how to achieve iSCSI on an AIX host through Cisco MDS across the storage area network (SAN. These procedures also describe some interface optimization parameters.

Introduction

Cost-effective storage solutions do not require any new content. Internet small computer system interface (iSCSI) is also not new content, but when we start to implement iSCSI across js20 blade centers on AIX, iSCSI seems to be new content.

This document explains how to implement iSCSI on AIX through the Cisco MDS switch. This section describes all the steps for configuring the host and SAN Switch of a Cisco MDS-type SAN Switch. The information in this article is based on practical experience. We assume that you have mastered the configuration skills of Aix system management and Cisco Storage Area Network (SAN.

The steps in this process are related to the Cisco fabric Manager configuration, Cisco Device Manager configuration, and Aix host configuration. We also provide the AIX optimization part, which is optional, but we recommend that you do so.

Prerequisites

The process for configuring iSCSI on AIX assumes that the following conditions are met:

• AIX version 5.2 or later is installed on the server or host node.
• Cabling of all networks and optical fibers has been completed.
• Most importantly, the network configuration has been completed and tested, including the ability to perform Ping tests from the AIX node to the iSCSI IP address.

Basic configurations include: Four js20 server nodes are connected through the Cisco Catalyst network switch, and the Cisco Catalyst Network Switch is bridge to the storage through the Cisco MDS 9000 SAN Switch. In this application, two IBM DS-4800 have been used as back-end storage.

Cisco fabric Manager

Users need to have administrator access permissions and knowledge of application partitions to create the required regions for host nodes and backend storage. To enable iSCSI on a Cisco mds san Switch from Cisco fabric manager, perform the following operations:

1. InPhysical attributes(Lower left) on the MDS pane, selectEnd devices> iSCSI.
2. Select All vswitches in the NetworkControlTab, and then selectIscsi enable.
3. SelectApply.

Partition

Partition execution on the Cisco fabric manager graphical user interface (GUI) should be performed in the same way as any other device. Once the MDS is set to process the iSCSI interface, the MDS should be considered as any other terminal device.

Cisco Device Manager

Use Device Manager on the Cisco mds san Switch to perform the following steps. You need to have administrator access and knowledge about how to configure the MDS vswitch through the Device Manager GUI. We recommend that you have a general knowledge about San (including partitions ).

Perform the following operations on the initial MDS settings:

1. Enable on Cisco mds san SwitchIscsi licenseFunction.
2. On the MDSAdminSelectFeature Control.
3. EnableIscsi-vsan-interface-Membership.
4. SelectApply.

In this case, the Cisco MDS switch can accept iSCSI commands at any time.

Now, you will set the MDS port and parameters. To configure the gige interface, perform the following operations:

1. Find the Cisco Catalyst Network SwitchISCSIPort.
2. Right-click the port to be configured and selectConfigure....
3. Select from the top of the configuration panelGigeTab.
4. InDescriptionEnter the port description in the field.
5. Change MTU9000. (For better performance, we recommend that you change MTU to 9000, but this setting is optional .)
6. InIP address/maskEnter the IP address and subnet for the iSCSI port.

The Cisco Catalyst network switch automatically fills in the subnet mask at the end of the IP address. If the subnet you are using is different from the subnet already assumed by Cisco, you can change it manually.

1. FromIscsiauthmethodSelectNoneOrChapTo select the auth method.
2. SelectApply.

After completionEachTab to apply all changes.ApplyThe button only saves the changes to the tabs You are currently using. This button will not be applied to other tabs.

To configure the iSCSI interface, perform the following operations:

1. Select from the top of the configuration panelISCSITab.
2. InDescriptionEnter the port description in the field.
3. Select an appropriate virtual storage area network (vsan) for portvsan from the drop-down list, or enter an appropriate vsan number.
4. InInitiator proxy ModeSelectEnableBox.
5. IsAssignmentOption SelectionAuto.
6. SelectApply.

To configure the iscsi_tcp interface, perform the following operations:

1. Select from the top of the configuration panelIscsi_tcpTab.
2. IsLocaltcpportEnter the correct value.
3. SelectApply.

Perform the following operations on the MDS Initiator/Target settings:

1. SelectIscsi....
2. InInitiatorTab, selectCreate.
3. InISCSI initiator CreationSet the iSCSI node name or IP address and vsan member identity.
4. InPort WWN MappingSelectPersistentBox.
5. SelectTargetsTab, and then selectCreate.
6. InIscsi nameEnter the appropriate name of the target in the field.
7. IsInitiator access listingSelectAll.
8. SelectAll, Or fromAdvertised InterfacesSelect an appropriate interface from the list field.
9. SelectApply.

AIX Host Configuration

You need to have the root-level authorization and the application knowledge of Aix system management.

To use ds4000 series back-end storage, the following ODM items are required. Other storage devices may need their own ODM items, but they need to handle such situations one by one. Make sure that the following ODM items are provided and the ODM is connected to a ds4000 storage device.

array.iscsi.ibm-dac-V4.add

If not, issue the following command from the command line:

odmadd array.iscsi.ibm-dac-V4.add

To configure the iscsi0 interface, you must create a unique network interface for iSCSI. Use Smit and enter:

smitty -> chgiscsisw

Enter the iscsi0 short name. For example:

iqn.com.ibm.po.ppd.z19c3s11e3.hostid.0972f5ec

Enter the following command from the command line:

chdev –l iscsi0 –a initiator_name=iqn.com.ibm.pok.ppd.

Iqn.com. IBM. Pok. PPD is not typed incorrectly; it is the method by which iSCSI resolves the target storage name. Use

/Etc/iSCSI/targets configuration file

The/etc/iSCSI/targets file has the required entries. The/etc/iSCSI directory contains a targets file, which requires entries for each iSCSI target port, as described in Cisco device manager. These entries must be created in the format shown in Listing 1 below. The targets file also provides examples of access and authorization levels.

Listing 1. Examples of the/etc/iSCSI/targets File

################################################################## # EXAMPLE 1: iSCSI Target without CHAP(MD5) authentication # Assume the target is at address 192.168.3.2, # the valid port is 5003 # the name of the target is iqn.com.ibm-4125-23WTT26 # The target line would look like: # 192.168.3.2 5003 iqn.com.ibm-4125-23WWT26 192.169.240.8 5003 iqn.com.ibm.pok.ppd.zec1xbba3.0005 192.169.240.16 5003 iqn.com.ibm.pok.ppd.zec1xbbb3.0006 # 192.169.240.1 5003 iqn.com.ibm.pok.ppd.zec2xbba1.0003 # 192.169.240.1 5003 iqn.com.ibm.pok.ppd.zec2xbbb1.0004 # # EXAMPLE 2: iSCSI Target with CHAP(MD5) authentication # Assume the target is at address 10.2.1.105 # the valid port is 3260 # the name of the target is iqn.com.ibm-K167-42.fc1a # the CHAP secret is "This is my password." # The target line would look like: # 10.2.1.105 3260 iqn.com.ibm-K167-42.fc1a "This is my password." # # EXAMPLE 3: iSCSI Target with CHAP(MD5) authentication and line continuation # Assume the target is at address 10.2.1.106 # the valid port is 3260 # the name of the target is iqn.2003-01.com.ibm:00.fcd0ab21.shark128 # the CHAP secret is "123ismysecretpassword.fc1b" # The target line would look like: # 10.2.1.106 3260 iqn.2003-01.com.ibm:00.fcd0ab21.shark128 / # "123ismysecretpassword.fc1b" # #####################################################################

Enter each target (storage) address created in MDS in the following format:

192.169.240.1 5003 iqn.com.ibm.pok.ppd.z20c4s11e3.hostid.0972f5ec

Where:

• 192.169.240.1 is the IP address of the iSCSI port.
• Iqn.com. IBM. Pok. PPD is the DNS target address of iSCSI.
• Z20c4s11e3 is the en3 interface of the host.
• Hostid is input by the user.
• 0972f5ec is input by the user.

Run ipvmgr-v.

Execute the lspv command on each AIX node and ensure that these nodes can access all available storage.

Optional host configurations

To achieve better performance on iSCSI, we recommend that you set the following interface optimization parameters:

tcp_recvspace=262144 tcp_sendspace=262144 rfc1323=1 jumbo frames = yes

Command Line input process:

ifconfig en3 down ifconfig en3 detach chdev –a ent3 –a jumbo_frames=yes chdev –l en3 –a tcp_recvspace=262144 chdev –l en3 –a tcp_sendspace=262144 chdev –l en3 –a rfc1323=1 ifconfig en3 up

Conclusion

After completing the steps described in this article, you should have access to the configured backend storage. Continue to the next step to verify whether all storage is provided and accessible.