HP-UX iSCSI Software Initiator Support Guide (Edition 7)

Table 6 Software Interface Driver Statistics (continued)
Description of FieldCLiscsiutil Statistic
that some outbound command, or a NOP-OUT in response to
a NOP-IN, could not be completed. As a result:
— The regular occurrence of this event will have a negative
impact on performance.
— Failed I/Os will be retried according to existing SCSI retry
policies (same as Fibre Channel and parallel SCSI),
however, there is no retry policy for native iSCSI commands.
The number of streams message memory allocation attempts
that failed. The regular occurrence of this event will have a
DNumber of streams message allocation
failures
negative impact on performance. Failed I/Os will be retried
according to existing SCSI retry policies (same as Fibre
Channel and parallel SCSI).
The number of transmission attempts of native iSCSI commands
that failed, because the connection on which the I/O was
DNumber of PDU transmission failures due to
an offline connection
attempted, was offline. The regular occurrence of this event
will have a negative impact on performance. Failed I/Os will
be retried according to existing SCSI retry policies (same as
Fibre Channel and parallel SCSI).
The number of streams message duplication operations that
failed. As a result of the failure, the iSCSI Software Initiator
DNumber of streams message duplication
failures
will not transmit the related iSCSI commands. The regular
occurrence of this event will have a negative impact on
performance. Failed I/Os will be retried according to existing
SCSI retry policies (same as Fibre Channel and parallel SCSI).
The number of iSCSI PDUs successfully transmitted to the target
for which no response was received within a specified period
D/C/TNumber of PDU exchange timeouts
of time. If a timeout occurs, the iSCSI Software Initiator will
initiate a logout for the session as part of the recovery, and
eventually will attempt to login again with the target. The
problem could be a network infrastructure problem or a target
congestion issue. The regular occurrence of this event will have
a negative impact on performance. Failed I/Os will be retried
according to existing SCSI retry policies (same as Fibre
Channel and parallel SCSI).
The number of iSCSI PDUs that were aborted by the initiator
while waiting for a response from a target. The abort occurs
C/TNumber of PDU exchanges aborted
if a response to the iSCSI PDU has not been received at the
initiator within a preset timeout period. The failure can also
be due to an unexpected close of the TCP connection. The
problem could be a network infrastructure problem or a target
congestion issue.
The number of exchanges between an iSCSI initiator and target
that were abandoned. This will typically occur when the
D/TNumber of PDU exchanges abandoned
number of exchanges to complete a negotiation goes beyond
a predetermined limit, usually indicating an infinite loop.
The number of SCSI I/Os that were sent to the networking
stack by the iSCSI Software Initiator.
INumber of I/Os issued on this connection
The number of SCSI I/Os that did not complete within a time
period preset by an upper level protocol (SCSI). The driver
D/TNumber of I/O timeouts
will recover from SCSI I/O timeouts using session level error
recovery, for example, tearing down the session and starting
over. Failed I/Os will be retried according to existing SCSI
retry policies (same as Fibre Channel and parallel SCSI).
The number of kernel memory allocation failures for SCSI I/O
related data structures. Failure to allocate will result in the I/O
DNumber of kernel memory allocation failures
not being processed and returned to the SCSI layer. The
D.1 iSCSI Software Interface Driver Statistics 55