User`s guide

11 – Updating the HBA
Configuring an HBA’s Firmware Values
IS0054602-00 A 11-5
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❑ Connection Keep Alive Timeout. This column indicates the time interval
(in seconds) between connection keep-alive pings. When a connection is
idle for the connection keep-alive timeout interval, the QLA4xxx HBA sends
an NOP ping to the other device that is part of the connection. When the
device responses to the ping, the connection remains open. When the
device fails to respond, the QLA4xxx HBA closes the connection and
informs the driver that the connection has gone down. The maximum
keep-alive time is 18 hours.
❑ Ethernet Pause. When this check box is selected, the QLA4xxx HBA
accepts pause frames from a connected device. In addition, the QLA4xxx
HBA will issue an Ethernet pause to momentarily stop incoming traffic when
the SDRAM is almost full. This feature is not currently supported.
❑ Header Digest. When this check box is selected, iSCSi headers with CRC
protection can be transmitted. In addition, incoming iSCSI headers are
validated and the CRC protection removed.
❑ Data Digest. When this check box is selected, iSCSi data with CRC
protection can be transmitted. In addition, incoming iSCSI data is validated
and the CRC protection removed.
❑ ARP Redirect. When this check box is selected, MAC addresses are
discovered and bound to IP addresses for hosts to which the QLA4xxx
HBA wants to talk.
❑ Error Recovery Level. When this check box is selected, the QLA4xxx
HBA supports iSCSI error recovery level 0. At this level, the QLA4xxx HBA
closes a connection if it detects any errors.
❑ Nagle. When this check box is selected, the QLA4xxx HBA supports the
Nagle algorithm. Therefore, when a TCP connection has outstanding data
that has not been acknowledged (ACKed), small data segments cannot
be sent until the ACKs arrive. These data segments are collected by TCP
and sent in a single segment when the ACKs arrive. This feature helps
control congestion.
❑ TCP Timestamp. When this check box is selected, a timestamp is placed
in every transmitted TCP segment. When the receiver responds with an
acknowledge (ACK), the timestamp is included. Consequently, the
transmitter can calculate the round trip time (RTT) of the ACK. This value
is used in calculating retransmissions (if necessary). When this check box
is not selected, RTT can only be calculated on one outstanding segment
at a time (rather than on each segment).
❑ Strict iSCSI Login. When this check box is selected, the QLA4xxx HBA
adheres to the iSCSI login rules, and therefore cannot operate with devices
that do not conform to these rules. When this check box is not selected,
the iSCSI login rules are relaxed, and the QLA4xxx HBA can operate with
devices that do not conform to these rules.