Table Of Contents
Release Notes for Cisco iSCSI Driver Version 3.2.1 for Linux
May 30, 2003
Note You can find the most current documentation on Cisco.com. This set of electronic documents may contain updates and modifications made after the hard-copy documents were printed.
These release notes support Cisco iSCSI Driver version 3.2.1 for Linux.
For a list of software caveats that apply to version 3.2.1, see the "Caveats" section. The caveats are updated for every maintenance version and are located on Cisco.com and the Documentation CD-ROM.
These Release Notes describe the following topics:
The Cisco iSCSI Driver for Linux provides an IP host with the ability to access storage through an IP network. The iSCSI driver uses the iSCSI protocol to transport SCSI requests and responses over an IP network between the IP host and a Cisco SN 5400 or MDS 9000 Series system.
Architecturally, the iSCSI driver combines with the IP host's TCP/IP stack, network drivers, and network interface cards (NICs) to provide the same functions as a SCSI or Fibre Channel adapter driver with a host bus adapter (HBA).
The iSCSI driver provides a transport for SCSI requests and responses for storage devices; however, instead of providing a transport for directly attached devices, the driver transports the SCSI requests and responses between the IP host and a Cisco SN 5400 or MDS 9000 Series system via an IP network. The SN 5400 or MDS 9000 Series system, in turn, transports SCSI requests and responses between it and the storage devices attached to it.
Once the iSCSI driver is installed and started, the host proceeds with a discovery process for storage devices.
A more technical description of the driver's design and its features can be found in the readme file that accompanies the iSCSI driver in the downloaded driver archive file.
Note The iSCSI protocol is an IETF-defined protocol for IP storage (ips). For more information about the iSCSI protocol, refer to the IETF standards for IP storage at http://www.ietf.org.
This section describes the system requirements for version 3.2.1 and includes the following information:
Operating System Requirements
•This driver requires a Linux kernel version 2.4.16 or later, running on an Intel IA32 (80386, 80486, Pentium) or equivalent, processor. Compilation requires that the kernel header files match the kernel version you want to use the driver with. Once compiled, the objects and executables can be moved to another host running the same level of the operating system.
•If you are running a kernel binary compiled for you by a Linux vendor, the iSCSI driver must be compiled against the source code distributed by the Linux vendor, without any modifications. The process of compiling a custom kernel from source makes modifications to the files in the kernel source tree, and an iSCSI driver compiled against a modified kernel source tree may not run on a kernel binary distributed by the Linux vendor.
If you have already made changes to the kernel source tree and you wish to run the iSCSI driver on one of the vendor's kernel binaries, you will need to reinstall the kernel source code provided by the Linux vendor.
•The driver supports single-processor and multiprocessor machines.
•To ensure the best performance for iSCSI drivers, the extended windowing feature of TCP should be enabled on all IP hosts connecting to the SN 5400 Series system. In general, a larger window size enhances SN 5400 Series system performance.
•The receive and transmit flow control feature of the Gigabit Ethernet driver should be enabled on all IP hosts connecting to the SN 5400 Series system.
•Linux kernels released after January 11, 2003 may or may not work with this driver, depending on what changes have been made to the kernel's SCSI midlayer code. See the readme file for additional information about known problems with specific versions Linux kernel code.
Note Additional information about Linux kernel issues can be found in the Linux Kernel HOWTO document at http://www.linux.org/docs/.
SN 5400 Series System Software Requirements
The iSCSI Driver version 3.2.1 for Linux is interoperable with a Cisco SN 5400 Series system running software release 3.2.1 or later. This version of the driver is not interoperable with a Cisco SN 5400 Series system running software release 2.5.x or earlier.
MDS 9000 Series System Software Requirements
The iSCSI Driver version 3.2.1 for Linux is interoperable with a Cisco MDS 9000 Series system running SAN-OS Release 1.1(1) or later.
New and Changed Information
•Support for two-way CHAP (Challenge Handshake Authentication Protocol) authentication—Provides for two way authentication between the target and the initiator. The authentication feature on the SN 5400 system must be enabled to use this feature.
•Target portal failover—Enables the iSCSI driver to attempt to connect to a target using the next available IP address if an existing target connection fails. A "preferred portal" can also be specified.
•Multipath I/O software support—Allows third-party multipath I/O software applications to be used in conjunction with the iSCSI driver.
•Dynamic reconfiguration—Allows configuration changes to be made to the iSCSI driver without having to stop it or without having to reboot the system.
•The iSCSI driver now supports Red Hat Linux 9.0.
•Prior to version 3.2.1, the iSCSI driver used the file /var/iscsi/bindings instead of /etc/iscsi.bindings. The first time you start the new driver version, it will change the location and the name of the bindings file to /etc/iscsi.bindings.
•Prior to version 3.2.1, the iSCSI driver installation saved the /etc/iscsi.conf file as /etc/iscsi.conf.new. Starting with version 3.2.1, the iSCSI driver installation saves the /etc/iscsi.conf file as /etc/iscsi.conf.<version>.
See the readme file for additional information about all new features.
This section describes how to obtain iSCSI driver software and upgrade an existing iSCSI driver installation, and includes the following information:
Downloading the iSCSI Driver
Registered Cisco.com users can download the most current SN 5400 Series system software, Cisco iSCSI drivers, readme files and release notes from Cisco.com. In addition, information about driver compatibility and other relevant driver information is available on Cisco.com. You can access software and related information by following these instructions:
Step 1 At http://www.cisco.com, log in to Cisco.com. Click Technical Support and Software Center.
Step 2 At the Software Center web page, under Software Products & Downloads, click Storage Networking Software.
Step 3 At the Storage Networking Software web page, click the appropriate link for your software.
Step 4 At the Software Download web page, click the file that you want to download. Another software download web page will be displayed with detailed information about the download file and Cisco's Software License Agreement. Follow the instructions on that and any subsequent web pages to download the software.
Step 5 To install and configure storage router software, see the appropriate storage router software configuration guide and release notes. To install and configure an iSCSI driver, see the readme file that accompanies the iSCSI driver (in the downloaded driver archive file) and the appropriate release notes.
Configuration guides and release notes are available online. You can access online documentation by following these instructions:
Step 1 At http://www.cisco.com, click Products & Services and Storage Networking Products.
Step 2 At the Cisco Storage Networking Products web page, click Cisco SN 5400 Series Storage Routers.
Step 3 At the Cisco SN 5400 Series Storage Routers web page, click Technical Documentation. On the Technical Documentation web page, choose the appropriate link for documentation, release notes, or other related information.
Installing, Upgrading and Uninstalling iSCSI Driver Software
For complete procedures to install and configure, upgrade, or uninstall iSCSI driver software, refer to the readme file that accompanies the iSCSI driver (in the downloaded driver archive file).
Limitations and Restrictions
The Cisco iSCSI driver for Linux no longer supports a Linux kernel version 2.2.x. The iSCSI driver requires a 2.4.x Linux kernel version.
Caveats describe unexpected behavior or defects in the 3.2.1 version of the driver. Severity 1 caveats are the most serious caveats; severity 2 caveats are less serious.
There are no open or resolved severity 1 or 2 caveats for the iSCSI Driver version 3.2.1 for Linux.
Note If you have an account with Cisco.com, you can use Bug Navigator II to find caveats of any severity for any version. You can reach Bug Navigator II on Cisco.com at Service & Support:
Cisco iSCSI driver troubleshooting information is available on the Cisco.com web site.
You can access troubleshooting information by following these instructions:
Step 1 At http://www.cisco.com, log in to Cisco.com. Click Products & Services, and select Storage Networking Software from the menu.
Step 2 At the Cisco Storage Networking Software web page, click Cisco iSCSI Drivers, and then click Technical Documentation.
Step 3 At the Technical Documentation web page, click the Tech Notes link.
Step 4 At the Tech Notes page, click the appropriate link for your iSCSI driver.
You can access iSCSI driver FAQs by following these instructions:
Step 1 At http://www.cisco.com, log in to Cisco.com. Click Products & Services, and select Storage Networking Software from the menu.
Step 2 At the Cisco Storage Networking Software web page, click Cisco iSCSI Drivers, and then click Product Literature.
Step 3 At the Product Literature web page, click the Q&A link.
Step 4 At the Q&A page, click the appropriate link for your iSCSI driver.
The following sections describe the related documentation available for the iSCSI Driver version 3.2.1 for Linux, and the Cisco SN 5400 and MDS 9000 Series systems. These documents consist of the iSCSI driver release notes and readme file, and the SN 5400 and MDS 9000 Series system hardware installation and software configuration guides.
The SN 5400 and MDS 9000 Series system hardware installation and software configuration documentation sets are available as printed manuals or electronic documents. The iSCSI driver readme file is available in electronic format, as part of the software download package. See the "Downloading the iSCSI Driver" section for details.
This Release Notes document is the only document specific to iSCSI Driver version 3.2.1 for Linux. It is located on Cisco.com and the Documentation CD-ROM.
Each release of SN 5400 and MDS 9000 Series system software includes an associated Release Notes document, which is also available as an electronic document on Cisco.com and the Documentation CD-ROM.
Refer to the appropriate SN 5400 or MDS 9000 Series system hardware installation guide for hardware installation procedures. The Cisco SN 5428 Storage Router Hardware Installation Guide provides hardware installation procedures for SN 5428 Storage Routers. The Cisco SN 5428-2 Storage Router Hardware Installation Guide provides hardware installation procedures for SN 5428-2 Storage Routers. These documents are available as printed manuals. They are also available as electronic documents on Cisco.com and the Documentation CD-ROM
Refer to the appropriate SN 5400 or MDS 9000 Series system software configuration guide for software configuration information. The Cisco SN 5428 Storage Router Software Configuration Guide Release 3.2 (or later) provides configuration information for SN 5428 Storage Routers. The Cisco SN 5428-2 Storage Router Software Configuration Guide Release 3.2 (or later) provides configuration information for SN 5428-2 Storage Routers. These documents are available as printed manuals. They are also available as electronic documents on Cisco.com and the Documentation CD-ROM.
For documentation on the SN 5400 Series system web-based GUI, refer to the SN 5400 Series system web-based GUI online Help system.
Service and Support
For service and support for a product purchased from a reseller, contact the reseller, who offers a wide variety of Cisco service and support programs described in "Service and Support" of Cisco Information Packet shipped with your product.
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For service and support for a product purchased directly from Cisco, use Cisco.com.
Software Configuration Tips on the Cisco TAC Home Page
A variety of Cisco SN 5400 Series system software and iSCSI driver installation, configuration and usage tips are available on the Cisco Technical Assistance Center (TAC) Web Site.
You can access "tech tips" by following these instructions:
Step 1 At http://www.cisco.com, log in to Cisco.com. Click Technical Support, and select Hardware Support from the menu.
Step 2 At the Hardware Support web page, click Storage Networking Devices from the Hardware Support menu on the left side of the page.
Step 3 At the Storage Networking Devices web page, click the appropriate link for your system. For example, click the SN 5428 Storage Routers link.
Step 4 Click the Troubleshooting link, and then click the appropriate links for information about installing, configuring, and troubleshooting SN 5400 Series system software and iSCSI drivers.
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This document is to be used in conjunction with the documents listed in the "Related Documentation" section.
Copyright © 2003 Cisco Systems, Inc. All rights reserved.