Dell Broadcom NetXtreme Family of Adapters Broadcom NetXtreme 57XX User Guide - Page 33
Making Connections to iSCSI Targets, Maximize Offload iSCSI Connections, Linux iSCSI Offload FAQ - broadcom v 7 100
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By default, the open-iscsi daemon connects to discovered targets using software initiator (transport name = 'tcp'). Users who wish to offload iSCSI connection onto CNIC device should explicitly change transport binding of the iSCSI node. This can be done using iscsiadm cli utility as follows, iscsiadm --mode node --targetname iqn.2004-06.com.broadcom:tg1 \ --portal 192.168.1.100 --op=update \ --name=node.transport_name --value=${XPORT_NAME} where XPORT_NAME=bcm570x-xxyyzz xx - pci bus number of the NX2 device yy - pci device number of the NX2 device zz - pci function number of the NX2 device Network interface to iscsi transport name binding can be obtained by executing the following. dmesg | grep "bnx2i: netif" Sample output in a system with two NetXtreme II devices: bnx2i: netif=eth1, iscsi=bcm570x-050000 bnx2i: netif=eth0, iscsi=bcm570x-030000 If you wish to switch back to use the software initiator, use the following: iscsiadm --mode node --targetname iqn.2004-06.com.broadcom:tg1 \ --portal 192.168.1.100 --op=update \ --name=node.transport_name --value=tcp Making Connections to iSCSI Targets Refer to open-iscsi documentation for a comprehensive list of iscsiadm commands. This is a sample list of commands to discovery targets and to create iscsi connections to a target. Add static entry iscsiadm -m node -p -T iqn.2007-05.com.broadcom:target1 -o new iSCSI target discovery using 'SendTargets' iscsiadm -m discovery --type sendtargets -p Login to target using 'iscsiadm' command iscsiadm --mode node --targetname --portal --login List all drives active in the system 'fdisk -l' Maximize Offload iSCSI Connections With default driver parameters set, which includes 128 outstanding commands, bnx2i can offload a maximum of 28 iSCSI connections. This is not a hard limit, but just a simple on-chip resource allocation math. bnx2i will be able to offload > 28 connections by reducing the shared queue size which in turn limits the maximum outstanding tasks on a connection. Driver logs the following message to syslog when the maximum allowed connection offload limit is reached - "bnx2i: unable to allocate iSCSI context resources" Linux iSCSI Offload FAQ Not all Broadcom NetXtreme II adapters support iSCSI offload. The iSCSI session will not recover after a hot remove and hot plug. The iSCSI driver/firmware will not offload iSCSI connections onto a jumbo frame-enabled CNIC device. For MPIO to work properly, iSCSI nopout should be enabled on each iSCSI session. Refer to open-iscsi documentation for procedures on setting up noop_out_interval and noop_out_timeout values. In the scenario where multiple CNIC devices are in the system and the system is booted via Broadcom's iSCSI boot solution, ensure that the iscsi node under /etc/iscsi/nodes for the boot target is bound to the NIC that is used for booting. Please read all Restrictions and Disclaimers.