Troubleshooting Undetected Target Devices

Verify that all of the required patches or superseding patches for the iSCSI Software Initiator have been installed. Review the HP-UX iSCSI Software Initiator Release Notes to obtain a list of required patches.
If a target device cannot be seen from the HP-UX host, verify that the problem is not an infrastructure connectivity issue by executing the /usr/sbin/ping command from the HP-UX host, specifying the IP address or qualified domain name of the iSCSI target. If ping is not successful, verify that the target device is available, powered on, and properly connected to the network.

If the iSCSI discovery target does not appear to respond:

Verify that the IP address or domain name of the discovery target was entered correctly by executing: iscsiutil -p -D

Verify that the iSCSI Name is valid.

The iSCSI Initiator Name or iSCSI Target Name is referred to as an iSCSI Name. The iSCSI Software Initiator configures a default Initiator Name in the "iqn" format. If you have changed the Initiator Name from its default using iscsiutil and the Initiator Name is in an invalid format, iSCSI login negotiation could fail leaving target devices inaccessible from the HP-UX host.

The iSCSI Software Initiator validates iSCSI Names. If a target reports a Target Name in an "iqn", "eui" or "naa" format, but it does not comply with the iSCSI Name format rules, or if a Target Name contains a prohibited character, iSCSI Login negotiation will fail and the target will not be seen by the HP-UX host.




	NOTE: The iSCSI Name format rules are detailed in “Configuring the iSCSI Software Initiator”. Prohibited characters are described in section 6.2 of RFC 3722, "String Profile for Internet Small Computer Systems Interface (iSCSI) Names". Consult RFC 3722 at: `http://www.ietf.org/rfc/rfc3722.txt`

The following characters MUST NOT be used in iSCSI names:

0000-002C; [ASCII CONTROL CHARACTERS and SPACE through , ]

002F; [ASCII / ]

003B-0040; [ASCII ; through @ ]

005B-0060; [ASCII [ through ‘ ]

007B-007F; [ASCII { through DEL]

You will need to work with the target vendor representative to correct an invalid Target Name format.

Verify that the fully qualified domain name, or the hostname, of the discovery target is known (if used instead of IP address) using nslookup.
Confirm the TCP port and Target Portal Group Tag are correct for the iSCSI discovery target in question. The values entered, or used by default by the iSCSI Software Initiator, can be seen by executing: iscsiutil -p -D

Verify that the steps listed in “Configuring the iSCSI Software Initiator”, have been followed correctly and completed successfully.
Issue the iscsiutil -sG command and look at the following statistics:
- Number of Discovery session open failures
  If there is a non-zero value for this statistic, determine the cause of failure by either looking at the message logged in the /var/adm/syslog/syslog.log file or by monitoring the EMS/STM log files. The most common cause for failure would be an incorrect configuration of the components of the iSCSI target address:
  <ip-address>, <tcp-port> and <portal-grp-tag> or an iSCSI Login Negotiation failure.
- Number of Normal session open failures
  If there is a non-zero value for this statistic, determine the cause of failure by either looking at the message logged in the /var/adm/syslog/syslog.log file or by monitoring the EMS/STM log files. The most common cause for failure would be an incorrect configuration of the authentication and digest methods. Refer to Appendix A “Login Key Configuration”, for configuration steps.
- Number of SCSI INQUIRY commands issued that failed
  If there is a non-zero value for this statistic, determine the cause of failure by either looking at the message logged in the /var/adm/syslog/syslog.log file or by monitoring the EMS/STM log file. Some of the causes for failure are:
  The iSCSI session and/or connection is not in an online state, resulting in the SCSI Inquiry command not being sent to the target.
  The target device terminated the SCSI Inquiry command with a Check Condition, Busy, or Reservation Conflict status.
  The target device did not respond to the SCSI Inquiry command sent by the initiator within a stipulated amount of time.
  The target failed to execute the SCSI Inquiry command.
  The SCSI Inquiry command could not be issued due to memory resource constraints.
  Review the detailed "Cause and Action" messages logged in the EMS/STM log file and take the necessary action.
Target devices will not be seen if there are iSCSI Login Negotiation failures. Some of the causes for login failures are; protocol violation by the target, initiator login errors, or lack of memory on the initiator.
Determine the cause of login failures by either looking at the message logged in the /var/adm/syslog/syslog.log file or by monitoring the EMS/STM log file.
The detailed “Cause and Action” messages logged in the EMS/STM log file provide guidance on the necessary action to take. If EMS/STM is not set up and the only source of message logging is syslog.log, review the “Diagnostic Messages”, to determine the action to be taken.
iSCSI uses ext_bus instances from the same pool as Fibre Channel and Parallel SCSI. HP-UX is limited to 256 total allocations of ext_bus instances. The addition of iSCSI busses is a use of this resource. If you see the “Attempt to allocate more than the maximum number of sessions” message in the /var/adm/syslog/syslog.log file, the number of targets attached to the HP-UX system may need to be reduced, or if there are unused bus instance entries, it may be necessary to change (compress) bus instance assignments. This should only be done with the assistance of an HP support representative. Contact HP support for further assistance.
When authentication is desired, if some targets are not seen due to authentication failure:
- Verify that the iradd daemon is running (if Bi-Directional CHAP authentication is desired).
- Verify that the configuration steps in “Challenge-Handshake Authentication Protocol (CHAP) Configuration”, are followed.
When SLP based discovery is used and some targets are not seen in spite of the iSCSI islpd daemon starting successfully (as per the /etc/rc.log and /var/adm/syslog/syslog.log files), please verify the SLP configuration on the iSCSI target.

Troubleshooting Undetected Target Devices

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