Broadcom NetXtreme II

User Guide NetXtreme II
January 2010
Broadcom Corporation
Document ENGSRVT52-CDUM100-R Linux iSCSI Offload Page 139
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. See
Setting Values for Optional Properties for information on sq_size and rq_size. 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.
• 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.