HP-UX iSCSI Software Initiator Support Guide, HP-UX 11i v1 and 11i v2, July 2005

Appendix B

Transport Statistics

Transport statistics are explained in Table B-1, “Transport Statistics,” on page 88.

The Class column (CL) provides message classification. Messages can be informational (I), target errors (T),

transient driver errors (D), or connectivity problems (C).

Informational Messages are counters for driver events. They are not an indication of an error, but should

an error occur, they may provide some profiling information.

Target Errors are detected at the initiator and should be reported to HP and/or the target vendor. Not all

target errors are reported on the host side, and it is the responsibility of the system administrator to monitor

any device specific logs for target issues.

Transient Driver Errors typically occur when some resource, for example, memory, is in short supply, or

something is not configured correctly. The error is considered transient, because a retry of the operation, or a

correct re-configuration, is typically successful. I/Os that experience transient errors are retried, so no data is

lost. Control operations such as an application open, or a task management command, may not be retried (the

determination to retry is left to the application or to the administrator). If the system resource load is

increased, a small value for a transient driver error statistic may be an indication of problems. Larger values

for the transient driver error statistic will start to impact performance.

Connectivity Problems are typically network or target availability problems. Connectivity problems are

transient in the sense that a network infrastructure engineer can resolve the problem and I/O traffic will

resume as before.

Table B-1 Transport Statistics

iscsiutil Statistic CL Description of Field

Transport Global Statistics

Number of ioscan’s issued I The total number of times the iSCSI subtree

of nodes has been scanned.

Number of Discovery sessions

opened

I The number of discovery sessions that were

opened to discover new targets. A discovery

session is opened for each iSCSI target port

during an ioscan. A single ioscan would

therefore result in a separate discovery

session for each target port (portal group).