iSCSI Protocol: Broadcom NetXtreme II® Network Adapter User Guide
file:///C|/Users/Nalina_N_S/Documents/NetXtremeII/English/iscsi.htm[9/5/2014 3:45:06 PM]
Problem
: SLES 11 SP3 - iSCSI remote installation on 1 Gbps port of the 57800 NIC adapter fails with inbox driver. Loading
the external driver does not unload inbox bnx2x driver as well.
Solution
: Enter or append the following syntax
bnx2x.num_vfs=0
in the command prompt at the initial installation in order to
prevent the inbox bnx2x driver from loading. Example: at step 7b in the
Linux iSCSI Boot Setup
section, enter:
withiscsi=1 netsetup=1 bnx2x.num_vfs=0
iSCSI Crash Dump
If you will use the Broadcom iSCSI Crash Dump utility, it is important to follow the installation procedure to install the iSCSI
Crash Dump driver. See
Using the Installer
for more information.
iSCSI Offload in Windows Server
iSCSI traffic may be segregated offload is a technology that offloads iSCSI protocol processing overhead from host processors
to the iSCSI host bus adapter to increase network performance and throughput while helping to optimize server processor
utilization.
This section covers Broadcom's iSCSI offload feature for the NetXtreme II family of network adapters on Windows Server
systems. For Linux iSCSI offload, see
Linux iSCSI Offload
.
iSCSI Offload Limitations
The bnx2i driver for iSCSI does not operate on a stand-alone PCI device. It shares the same PCI device with the networking
driver (bnx2 and bnx2x). The networking driver alone supports layer 2 networking traffic. Offloaded iSCSI operations require
both the networking driver and the bnx2i driver.
iSCSI operations will be interrupted when the networking driver brings down or resets the device. This scenario requires
proper handling by the networking and bnx2i drivers, as well as the userspace iscsid daemon that keeps track of all iSCSI
sessions. Offloaded iSCSI connections take up system and on-chip resources that must be freed up before the device can be
reset. iscsid running in userspace is generally less predictable, as it can run slowly and take a long time to disconnect and
reconnect iSCSI sessions during network reset, especially when the number of connections is large. Broadcom cannot
guarantee that iSCSI sessions will always recover in every conceivable scenario when the networking device is repeatedly
being reset. Broadcom recommends that administrator-administered network device resets, such as MTU change, ring size
change, device shutdown, hot-unplug, and so forth, be kept at a minimum while there are active offloaded iSCSI sessions
running on that shared device. On the other hand, link-related changes do not require device reset and are safe to be
performed at any time.
To help alleviate some of the above issues, install the latest open-iscsi utilities by upgrading your Red Hat Network
subscription.
Configuring iSCSI Offload
With the proper iSCSI offload licensing, you can configure your iSCSI-capable NetXtreme II network adapter to offload iSCSI
processing from the host processor. The following process enables your system to take advantage of Broadcom's iSCSI
offload feature.
Installing Broadcom Drivers and Management Applications
Installing the Microsoft iSCSI Initiator
Configuring Broadcom iSCSI Using BACS
Configure Microsoft Initiator to Use Broadcom's iSCSI Offload
Installing Broadcom Drivers and Management Applications
Install the Windows drivers and management applications. See
Installing Windows Drivers and Management Applications.
Installing the Microsoft iSCSI Initiator
For Windows Server 2008 and later, the iSCSI initiator is included inbox. To download the iSCSI initiator from Microsoft, go to
http://www.microsoft.com/en-us/download/details.aspx?displaylang=en&id=18986
and locate the direct link for your system.
