Installation guide
AT-2973SX, AT-2973T, AT-2973T/4, and AT-VNC10S Adapters Installation and User’s Guide
75
Setting Optional Properties for the bnx2i Driver 
You can supply the optional parameters en_tcp_dack, error_mask1 and 
error_mask2 as command line arguments to the insmod or modprobe 
command for the bnx2i driver. 
error_mask1 and error_mask2 
Use “Config FW iSCSI Error Mask #” to configure certain iSCSI protocol 
violations to be treated either as a warning or a fatal error. All fatal iSCSI 
protocol violations result in session recovery (ERL 0). These are bit 
masks. By default, all violations are treated as errors. 
Caution
Do not use the error_mask parameter if you are not sure about the 
consequences. Discuss these values with the Broadcom 
development team on a case-by-case basis. This is a mechanism to 
work around iSCSI implementation issues on the target side and 
without proper knowledge of iSCSI protocol details, users are 
advised not to experiment with these parameters. 
en_tcp_dack 
The “Enable TCP Delayed ACK” parameter enables or disables the TCP 
delayed ACK feature on offloaded iSCSI connections. The TCP delayed 
ACK feature is ENABLED by default. To set the en_tcp_dack parameter in 
the bnx2i driver, enter one of the following commands:
insmod bnx2i.ko en_tcp_dack=0
or 
modprobe bnx2i en_tcp_dack=0
Default: ENABLED
sq_size 
Use the “Configure SQ size” parameter to select the send-queue size for 
offloaded connections. The SQ size determines the maximum SCSI 
commands that can be queued. Also, SQ size has a bearing on the 
number of connections that can be offloaded; as QP size increases, the 
number of connections supported decreases. With the default values, the 
AT-2973SX, AT-2973T, AT-2973T/4, and AT-VNC10S adapters can 
offload 28 connections. 
Defaults: 128 
Range: 32 to 128 










