HP-UX iSCSI Software Initiator Support Guide HP-UX 11i v1 & 11i v2 Edition 5 Manufacturing Part Number : T1452-90011 E0705 United States © Copyright 2005 Hewlett-Packard Development Company L.P..
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Contents About This Document ....................................................................................................................... 9 1. iSCSI Overview iSCSI Protocol Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The iSCSI PDU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iSCSI Layering . . . . . . . . . . . . . .
Contents Troubleshooting the iSCSI Software Initiator Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Undetected Target Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting issues with iswd daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tables Table 1. iSCSI Software Initiator Support Guide Publishing History . . . . . . . . . . . . . . . . . . . . . . . 10 Table 2-1. SLP Server Installation Information and Related Documents . . . . . . . . . . . . . . . . . . . . 27 Table 4-1. CHAP and RADIUS Server Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table B-1. Transport Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Table C-1.
Tables 6
Figures Figure 1-1. iSCSI: A Transport Protocol Alternative that Operates Over TCP/IP. . . . . . . . . . . . . . Figure 1-2. iSCSI Protocol Data Unit (PDU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 1-3. TCP Segment Data Area of an Ethernet Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 1-4. iSCSI Layering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 1-5.
Figures 8
About This Document This document describes how to install, configure, and troubleshoot the HP-UX iSCSI Software Initiator on HP-UX 11i v1 and HP-UX 11i v2 platforms. The document manufacturing part number (T1452-90011) and publication time frame (E0705), provide a unique identifier for this document and indicate when it was published. The manufacturing part number will change when a new edition is released. Document updates may be issued between editions to correct errors or document product changes.
Publishing History Table 1 Document Manufacturing Part Number iSCSI Software Initiator Support Guide Publishing History Operating Systems Supported Supported Product Versions Publication Date 5187-4536 11i v2 B.11.23.03 November 2003 5990-7213 11i v1 B.11.11.03a March 2004 11i v2 B.11.23.03a 11i v1 B.11.11.03b 11i v2 B.11.23.03b B.11.23.03c 11i v1 B.11.11.03d 11i v2 B.11.23.03d 11i v1 B.11.11.03e 11i v2 B.11.23.
1 iSCSI Overview This chapter contains information on: • “iSCSI Protocol Overview” on page 13 • “The iSCSI PDU” on page 14 • “iSCSI Layering” on page 15 Chapter 1 11
iSCSI Overview • “iSCSI Session and TCP Connections” on page 16 • “iSCSI Login” on page 17 • “iSCSI Concepts: Network Entities, Portals, and Nodes” on page 19 12 Chapter 1
iSCSI Overview iSCSI Protocol Overview iSCSI Protocol Overview NOTE Figure 1-1 This chapter provides a brief, high level, overview of the iSCSI Protocol as defined by RFC 3720. For comprehensive information on the iSCSI Protocol specification, consult RFC 3720 at: http://www.ietf.org/rfc/rfc3720.
iSCSI Overview The iSCSI PDU The iSCSI PDU iSCSI initiators and targets communicate with messages known as “iSCSI Protocol Data Units”. An iSCSI PDU has a Header and an optional Data Section. Figure 1-2 iSCSI Protocol Data Unit (PDU) iSCSI PDUs are transported in the TCP Segment Data Area of Ethernet Frames. The size of an iSCSI PDU is not dictated by the capacity of the TCP segment data area and an iSCSI PDU does not need to begin at a specific offset within a TCP segment data area.
iSCSI Overview iSCSI Layering iSCSI Layering iSCSI constructs Protocol Data Units (PDUs) consisting of SCSI commands, SCSI data and SCSI responses. iSCSI PDUs are inserted in the TCP segment data area of IP datagrams. The IP datagrams are then moved through the TCP/IP stack and transported over the network, between the SCSI services layer of host systems and the SCSI services layer of target storage devices.
iSCSI Overview iSCSI Session and TCP Connections iSCSI Session and TCP Connections In an iSCSI session, communication between an initiator and a target occurs over one or more TCP connections. The TCP connections carry control messages, data digests, SCSI commands, parameters, and data, all encapsulated in iSCSI Protocol Data Units (iSCSI PDUs). The TCP connections that link an initiator with a target, forming an iSCSI session, are comparable to a SCSI I_T nexus.
iSCSI Overview iSCSI Login iSCSI Login The iSCSI login enables: • A TCP connection for iSCSI use • Authentication of the parties • Negotiation of the session’s parameters • Marking the connection as belonging to an iSCSI session An iSCSI session is established to identify all of the connections between an initiator and a target belonging to the same I_T nexus.
iSCSI Overview iSCSI Login The iSCSI Login Phase consists of Login requests and responses. Once authentication has occurred and operational parameters have been set, the session transitions to the Full Feature Phase and the initiator begins performing SCSI I/Os. NOTE: Using authentication is optional. iSCSI parameters are negotiated using Login Requests and Responses, during session establishment. During the Full Feature Phase, iSCSI parameters are negotiated using Text Requests and Responses.
iSCSI Overview iSCSI Concepts: Network Entities, Portals, and Nodes iSCSI Concepts: Network Entities, Portals, and Nodes • Network Entity - a device or gateway that is accessible from the IP network. A network entity must have one or more network portals. Each network portal can be used by one or more iSCSI nodes within that network entity to gain access to the IP network.
iSCSI Overview iSCSI Concepts: Network Entities, Portals, and Nodes Figure 1-8 20 iSCSI Target Sharing Two Target Portal Groups Chapter 1
2 HP-UX iSCSI Software Initiator Product Overview Chapter 2 21
HP-UX iSCSI Software Initiator Product Overview This chapter contains information on: • “HP-UX iSCSI Software Initiator Features” on page 23 • “HP-UX iSCSI Software Initiator Components” on page 24 • “Targets” on page 25 • “Hardware Path Representation” on page 25 • “Device Discovery” on page 25 • “Static Discovery” on page 26 • “Service Location Protocol Based Dynamic Discovery” on page 26 22 Chapter 2
HP-UX iSCSI Software Initiator Product Overview HP-UX iSCSI Software Initiator Features HP-UX iSCSI Software Initiator Features • iSCSI Specification Compliance The iSCSI Software Initiator is based on the iSCSI Protocol Specification (RFC 3720). No attempt has been made to support any preliminary version of the iSCSI specification. For details, consult RFC 3720 at: http://www.ietf.org/rfc/rfc3720.
HP-UX iSCSI Software Initiator Product Overview HP-UX iSCSI Software Initiator Components HP-UX iSCSI Software Initiator Components The iSCSI Software Initiator has two kernel components: • iSCSI Transport Driver: the session management and transport module. • iSCSI Software Interface Driver: this module interfaces with the iSCSI Transport Driver and the host based TCP/IP stack. The iSCSI Software Initiator has four user space components: • iswd: A connection management daemon.
HP-UX iSCSI Software Initiator Product Overview Targets Targets The iSCSI Software Initiator is interoperable with all iSCSI Protocol Specification (RFC 3720) compliant targets. No component of the iSCSI Software Initiator implementation is, in any way, HP proprietary. The iSCSI Software Initiator supports the static discovery of targets and, optionally, the dynamic discovery of targets.
HP-UX iSCSI Software Initiator Product Overview Targets Static Discovery Static discovery requires the system administrator to identify all iSCSI discovery targets that will be accessible to an HP-UX host before an ioscan is executed. The configuration is done using the iscsiutil tool (see “The iscsiutil tool” on page 55, for details).
HP-UX iSCSI Software Initiator Product Overview Targets Figure 2-2 Service Location Protocol Once the operational targets are registered, the process used for static discovery of targets applies to them (starting from normal session establishment to operational targets), see “Static Discovery” on page 26. NOTE Table 2-1 SLP Server Installation Information and Related Documents Description url Service Location Protocol, version 2 (RFC 2608) http://www.ietf.org/rfc/rfc2608.
HP-UX iSCSI Software Initiator Product Overview Targets 28 Chapter 2
3 Installation This chapter contains information on: • “Locating and Installing the iSCSI Software Initiator” on page 31 • “iSCSI Software Initiator Components” on page 32 • “Kernel Build” on page 34 Chapter 3 29
Installation • 30 “Verifying the Installation” on page 35 Chapter 3
Installation Locating and Installing the iSCSI Software Initiator Locating and Installing the iSCSI Software Initiator The iSCSI Software Initiator is located at the HP Software Depot. 1. Go to http://www.software.hp.com. 2. Enter “iSCSI Software Initiator” in the “search” box. 3. When the search results show “iSCSI Software Initiator”, click on “Receive for Free”. 4.
Installation iSCSI Software Initiator Components iSCSI Software Initiator Components The iSCSI Software Initiator is composed of several files that will be copied to the appropriate directories on the host system during installation. The Software Distributor will add all of the following iSCSI files to HP-UX revision 11i v1 and HP-UX revision 11i v2 host configurations: • /usr/conf/lib/libiscsi.a This is the iSCSI library of 64 bit object modules that will be linked into the HP-UX kernel.
Installation iSCSI Software Initiator Components This is the iSCSI 64 bit object module containing debug information for Q4 dump analysis of the iSCSI Software Initiator. This module will be linked into the HP-UX kernel. • /usr/conf/master.d/iscsi This is the iSCSI master file.
Installation Kernel Build Kernel Build The SD tool will add the following iSCSI references to an HP-UX host configuration: • iscsial The iscsial statement in the /stand/system file results in the inclusion of the iSCSI adaptation layer in the kernel build. The adaptation layer is required for any iSCSI operation to be executed. • iscsi The iscsi statement in the /stand/system file results in the inclusion of the iSCSI transport layer in the kernel build.
Installation Verifying the Installation Verifying the Installation After the system reboots, verify that the installation was successful by following these steps: Step 1. Issue the swlist command as follows: # swlist iSCSI-00 If the HP-UX 11iv1 iSCSI Software Initiator is installed correctly, the generated output will look similar to this: # Initializing... # Contacting target "myhost"... # # Target: myhost:/ # # iSCSI-00 iSCSI-00.ISCSI-SWD B.11.11.03e B.11.11.
Installation Verifying the Installation 36 Chapter 3
4 Configuration This chapter contains information on: • “Configuring the iSCSI Software Initiator” on page 39 • “Challenge-Handshake Authentication Protocol (CHAP) Configuration” on page 43 • “Configuring CHAP Authentication Uni-directional” on page 44 Chapter 4 37
Configuration • “Configuring CHAP Authentication Bi-directional” on page 46 • “Starting the iradd (iSCSI CHAP) Daemon” on page 48 • “Configuring iSCSI Service Location Protocol (SLP) Scope” on page 50 38 Chapter 4
Configuration Configuring the iSCSI Software Initiator Configuring the iSCSI Software Initiator After the iSCSI Software Initiator has been installed and the system has been rebooted, the following iSCSI-specific tasks (in addition to network setup) must be done manually to complete the system setup: 1. Add the path for iscsiutil and other iSCSI executables to the root path as: # PATH=$PATH:/opt/iscsi/bin See “The iscsiutil tool” on page 55, for more information on iscsiutil. 2.
Configuration Configuring the iSCSI Software Initiator With the exception of the colon prefix, the owner of the domain name can designate the content of the optional string. It is the responsibility of the naming authority to ensure the iSCSI names it assigns are unique worldwide. For example, if the Hewlett-Packard Company owned the domain name "stor.hp.
Configuration Configuring the iSCSI Software Initiator # iscsiutil [/dev/iscsi] -a -I [-P ] [-M ] where -a adds a discovery target address into iSCSI persistent information. Only discovery target addresses can be added using this option. -I is the option that requires the IP Address or the Hostname of the discovery target portal address as an argument. is the IP Address or Hostname component of the target network portal.
Configuration Configuring the iSCSI Software Initiator AuthMethod (Authentication Method) The default value for HeaderDigest is: None,CRC32C The default value for DataDigest is: None,CRC32C The default value for AuthMethod is: None If you choose to configure any of the three user configurable login keys on a specific target, see Appendix A, “Login Key Configuration,” on page 81, for details on configuring the login keys.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration Challenge-Handshake Authentication Protocol (CHAP) is an authentication protocol that defines a methodology for authenticating initiators and targets. If you do not intend to use CHAP for authentication, this aspect of the iSCSI Software Intitator configuration is not necessary and can be ignored.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration NOTE Currently, AuthMethod is one of the three iSCSI login keys that may be configured by the user on a per target basis. The default value for AuthMethod is “None”. If you want to configure AuthMethod on a per target basis, see “Authentication Method Configuration Examples” on page 84.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration # iscsiutil -u -N [-T ] [-I ] ] [-P ] [-M If the CHAP initiator name is not configured, the iSCSI initiator name will be used instead. To configure the CHAP initiator name on a global basis: # iscsiutil -u -N mychapusername To configure the CHAP initiator username for a specific Discovery Target Address: # iscsiutil -u -N mychapusername -I 192.1.1.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration To display authentication parameters for all Sessions: # iscsiutil -pS To display authentication parameters for a particular Operational Target identified by its Target Name: # iscsiutil -p -T NOTE If authentication parameters are configured on a per target basis, the parameters displayed by "iscsiutil -l" are overridden by the parameters displayed by the other display commands.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration # iscsiutil -u -H CHAP_BI To configure Bi-directional authentication for a particular Discovery Target Address: # iscsiutil -u -H CHAP_BI -I 192.1.1.10 -M 3 To configure Bi-directional authentication for a particular Operational Target: # iscsiutil -u -H CHAP_BI -T iqn.2003-11.com.hp.stor:iSCSI To configure Bi-directional authentication for a particular Operational Target Address: # iscsiutil -u -H CHAP_BI -T iqn.200-1.com.hp.
Configuration Challenge-Handshake Authentication Protocol (CHAP) Configuration Starting the iradd (iSCSI CHAP) Daemon NOTE The Bi-directional CHAP method requires the use of the iradd daemon (iSCSI CHAP daemon). The Uni-directional CHAP method does not require the use of the iradd daemon (iSCSI CHAP daemon). To start the iradd daemon: # iradd Once the iradd daemon has been started, the iradd daemon will be restarted automatically each time the system reboots.
Configuration Configuring iSCSI Service Location Protocol Daemon "Start on Boot" Configuring iSCSI Service Location Protocol Daemon "Start on Boot" The iSCSI Software Initiator uses the iSCSI Service Location Protocol daemon (islpd) for SLPv2 based dynamic target discovery. By default, the islpd daemon is not started on boot. The user may configure the "Start on Boot" feature for islpd either to enable auto-start or disable auto-start of islpd daemon on boot.
Configuration Configuring iSCSI Service Location Protocol (SLP) Scope Configuring iSCSI Service Location Protocol (SLP) Scope The iSCSI Software Initiator uses SLP for dynamic Target Discovery. The SLP scope is used to control the availability of service advertisements. The iSCSI SLP User Agent (UA) can be configured with one or more scope strings. If no specific scope string is configured, the scope string will be "default". To configure the iSCSI SLP Scope List: 1.
5 Management This chapter contains information on: • “ioscan” on page 54 • “The iscsiutil tool” on page 55 • “iscsiutil Command Utilization” on page 55 Chapter 5 51
Management • “iSCSI Transport Statistics” on page 58 • “Diagnostic Messages” on page 59 • “iSCSI Software Initiator Daemons” on page 60 • “iSCSI Software Initiator Name Resolution Daemon (iscsi_resolvd)” on page 60 • “iSCSI Challenge-Handshake Authentication Protocol Daemon (iradd)” on page 60 • “iSCSI Service Location Protocol Daemon (islpd)” on page 60 52 Chapter 5
Management SAM SAM NOTE For detailed information about SAM, see Using System Administration Manager (SAM). This document can be viewed or downloaded at http://www.docs.hp.com, or a hard copy can be ordered from HP. The HP-UX System Administration Manager (SAM) has been modified to support the following iSCSI functionality: • Recognition of the iSCSI Software Initiator SAM will recognize the iSCSI virtual bus and display it under Peripheral Devices -> Device List.
Management ioscan ioscan After the iSCSI Software Initiator is installed, a virtual node will appear in the ioscan output. This virtual node will appear as follows: iscsi 0 255/0 When data is available for valid iSCSI targets, the output of the ioscan command for iSCSI targets will be similar to the following example: iscsi ext_bus target disk disk 0 2 5 2 3 255/0 255/0/0.0 255/0/0.0.0 255/0/0.0.0.0 255/0/0.0.0.
Management The iscsiutil tool The iscsiutil tool The iscsiutil command is a management and diagnostic tool used with the iSCSI Software Initiator. The iscsiutil tool provides a command line interface to: — Configure the iSCSI Software Initiator related parameters. — Display statistics for the interface driver, connection processing, session processing, and the discovery sequence. — Execute diagnostic functionality. Device files are automatically created to access the iSCSI transport and interface drivers.
Management The iscsiutil tool # iscsiutil [/dev/iscsi] -d -I [-P ][-M ] The ip_address specified can be an IPv4 formatted address or a DNS name A TCP port may be specified for the iSCSI target. If no port is specified, the default iSCSI target port (3260) will be used. The target portal group tag may be specified (a value from 0 to 65535 inclusive); otherwise a default value of 1 will be used.
Management The iscsiutil tool -S displays the session information for all sessions; if an initiator session identifier instance (ssn_inst) is specified, then information will be displayed for that session only. Session information displayed includes: - The session instance number. - The target iSCSI name. - The target IP address and port. - The target portal group tag.
Management iSCSI Transport Statistics iSCSI Transport Statistics The iSCSI Software Initiator maintains a variety of transport statistics, which are accessible through the iscsiutil tool. For a detailed listing and explanation of the iSCSI transport statistics see Appendix B, “Transport Statistics,” on page 87.
Management Diagnostic Messages Diagnostic Messages The HP-UX iSCSI Software Initiator works with HP-UX Event Monitoring Services (EMS) and the Support Tools Manager (STM). By default, the iSCSI Software Initiator logs all diagnostic messages to the STM log files. STM can be used to view the diagnostic messages logged in the STM log files. EMS can be configured to automatically notify the system administrator when diagnostic messages are logged by the iSCSI Software Initiator.
Management iSCSI Software Initiator Daemons iSCSI Software Initiator Daemons iSCSI Software Initiator Name Resolution Daemon (iscsi_resolvd) iscsi_resolvd is a user level daemon responsible for resolving a hostname to an IP address. This daemon operates by receiving hostnames from the iSCSI Software Initiator and returning the corresponding IP addresses to the iSCSI Software Initiator. This daemon is automatically started from the iSCSI Software Initiator start-up script during HP-UX system start-up.
6 Troubleshooting This chapter contains information on: • “Troubleshooting the iSCSI Software Initiator Installation” on page 63 • “Troubleshooting Undetected Target Devices” on page 64 • “Troubleshooting issues with iswd daemon” on page 67 Chapter 6 61
Troubleshooting • 62 “Diagnostics” on page 68 Chapter 6
Troubleshooting Troubleshooting the iSCSI Software Initiator Installation Troubleshooting the iSCSI Software Initiator Installation If you have attempted to install the iSCSI Software Initiator, but you suspect there is a problem, first review “Verifying the Installation” on page 35, to ensure the HP-UX iSCSI Software Initiator has been installed successfully. If the HP-UX iSCSI Software Initiator installation has failed, follow the techniques below to troubleshoot the issue. 1.
Troubleshooting Troubleshooting Undetected Target Devices Troubleshooting Undetected Target Devices 1. 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. 2.
Troubleshooting Troubleshooting Undetected Target Devices 4. Verify that the steps listed in “Configuring the iSCSI Software Initiator” on page 39, have been followed correctly and completed successfully. 5. 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.
Troubleshooting Troubleshooting Undetected Target Devices 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. 8. 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).
Troubleshooting Troubleshooting issues with iswd daemon Troubleshooting issues with iswd daemon The iswd daemon is involved in the connection management for the iSCSI Software Interface Driver. It opens and terminates TCP connections interfacing with the iSCSI Software Interface Driver. CAUTION The iswd deamon is required to access the iSCSI devices. To avoid upredictable results, the deamon must not be terminated.
Troubleshooting Diagnostics Diagnostics The HP-UX Support Tool Manager (STM) has been modified so a user can select the iSCSI virtual node entries in the STM map. However, when iSCSI devices are selected, all of the tools are grayed-out (not available). The HP-UX iSCSI Software Initiator works with HP-UX Event Monitoring Services (EMS) and the Support Tools Manager (STM). By default, the iSCSI Software Initiator logs all diagnostic messages to the STM log files.
7 The iSCSI Software Interface Driver This chapter contains information on: • “iSCSI Software Interface Driver Overview” on page 71 • “iSCSI Software Interface Driver Technical Overview” on page 72 • “System Startup” on page 72 Chapter 7 69
The iSCSI Software Interface Driver • “iSCSI Software Interface Driver Technical Specifications” on page 73 • “Features” on page 73 • “Limitations” on page 73 • “iSCSI Software Interface Driver Configuration” on page 74 • “Kernel Build” on page 75 • “iSCSI Software Interface Driver Management” on page 76 • “iSCSI Software Interface Driver Statistics” on page 77 • “iSCSI Software Interface Driver Diagnostic Messages” on page 78 • “iSCSI Software Interface Driver Daemons” on page 79 • “iSC
The iSCSI Software Interface Driver iSCSI Software Interface Driver Overview iSCSI Software Interface Driver Overview The HP-UX iSCSI Software Interface Driver (SWD) is a host based implementation of the iSCSI protocol that uses standard Network Interface Cards (NICs). There are no special network infrastructure requirements. The iSCSI SWD interfaces with the iSCSI transport layer for session management and SCSI support. It also interfaces with the network stack above the TCP layer.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Technical Overview iSCSI Software Interface Driver Technical Overview System Startup In the standard HP-UX system startup sequence, access to mass storage is established before networking is initialized. This order of events is in conflict with the iSCSI SWD, because iSCSI target devices cannot be accessed prior to networking initialization.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Technical Specifications iSCSI Software Interface Driver Technical Specifications Features • The iSCSI SWD conforms to the iSCSI Protocol Specification (RFC 3720). • The iSCSI SWD will function over standard NICs (Network Interface Cards). • The iSCSI SWD will be a compute-intensive driver. Limitations • The iSCSI SWD does not support the definition of the boot, root, primary swap, dump, or var volumes on iSCSI logical units.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Configuration iSCSI Software Interface Driver Configuration Existing networking commands must be used to establish routing information and LAN configuration for host based networking. The user is expected to understand the Service Location Protocol (SLP) dynamic scanning technique in order to use it. SLP is a software component separate from the iSCSI SWD.
The iSCSI Software Interface Driver Kernel Build Kernel Build The isw statement in the /stand/system file results in the inclusion of the iSCSI Software Interface Driver module, as well as the execution of the iswd daemon, during system startup.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Management iSCSI Software Interface Driver Management If the iscsiutil command is directed to the /dev/isw device file, the command is explicitly directed to the iSCSI SWD. Most command sequences require root or super user permission. The iscsiutil command can be used to: • Display the iSCSI Software Interface Driver statistics: # iscsiutil /dev/isw -s -G -G displays the iSCSI Software Interface Driver global statistics.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Statistics are maintained in the iSCSI Software Interface Driver (SWD). For a detailed listing and explanation of the iSCSI Software Interface Driver statistics see Appendix D, “iSCSI Software Interface Driver Statistics,” on page 105.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Diagnostic Messages iSCSI Software Interface Driver Diagnostic Messages The HP-UX iSCSI Software Interface Driver works with HP-UX Event Monitoring Services (EMS) and the Support Tools Manager (STM). By default, the iSCSI Software Interface Driver logs all diagnostic messages to the STM log files. STM can be used to view the diagnostic messages logged in the STM log files.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Daemons iSCSI Software Interface Driver Daemons iSCSI Software Interface Driver Daemon (iswd) The iSCSI SWD daemon, iswd, is a user level process that communicates with the iSCSI SWD component and the network sockets interface. The iSCSI SWD daemon will receive requests to open or close a connection, then it will use the existing application network socket interface to perform the connection open/close operation.
The iSCSI Software Interface Driver iSCSI Software Interface Driver Daemons 80 Chapter 7
A Login Key Configuration Appendix A 81
Login Key Configuration Configuring iSCSI Login Keys Configuring iSCSI Login Keys In accordance with the iSCSI protocol, an iSCSI initiator must negotiate iSCSI login keys with each iSCSI target to: — enable an iSCSI connection — authenticate the parties — negotiate the session’s parameters — mark the connection as belonging to an iSCSI session All of the iSCSI login keys configured by default by the iSCSI Software Initiator apply to all of the targets connected to the iSCSI host node.
Login Key Configuration Configuring iSCSI Login Keys [-M ]] The order in which the login values are listed in this command defines the order in which the iSCSI initiator proposes them to the target. The login keys and values are not case-sensitive. The configurable login keys currently available are: • HeaderDigest A header digest that can be negotiated during iSCSI login.
Login Key Configuration Configuring iSCSI Login Keys # iscsiutil -t datadigest CRC32C None -T iqn.2003-11.com. hp.stor:iSCSI.Storage Configure the HeaderDigest key with "CRC32C" as the value for an Operational Target Address: # iscsiutil -t headerdigest CRC32C -I 192.1.1.58 -M 2 -T iqn.2003-11.com.hp.stor:iSCSI.Storage Configure both the HeaderDigest and the DataDigest keys with "CRC32C" as the value for an Operational Target Address: # iscsiutil -t bothdigest CRC32C -I 192.1.1.58 -M 2 -T iqn. 2003-11.com.
Login Key Configuration Configuring iSCSI Login Keys To display login keys of a particular Operational Target identified by its Target Name: # iscsiutil -p -T Among the various login keys displayed by the commands described above, the parameters of interest are: • Authentication Method • Header Digest • Data Digest Displaying Negotiated Login Key Values After executing the "ioscan" command, which initiates a login negotiation, the following command can be executed to display the negotia
Login Key Configuration Configuring iSCSI Login Keys 86 Appendix A
B Transport Statistics Appendix B 87
Transport Statistics Transport Statistics 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.
Transport Statistics Transport Statistics Table B-1 Transport Statistics (Continued) iscsiutil Statistic Number of Discovery session open failures CL D/C Description of Field The number of attempted discovery sessions that failed. The failure is due to an inability to open a connection. Some of the reasons why a connection open might fail are: — Initiator/host name not configured. — Hostname could not be resolved (confirm that iscsi_resolvd daemon is running).
Transport Statistics Transport Statistics Table B-1 Transport Statistics (Continued) iscsiutil Statistic CL Description of Field Number of SendTargets commands issued I The number of iSCSI SendTargets commands sent to iSCSI targets. The iSCSI SendTargets command is used in discovery sessions to determine normal targets behind a target port (portal group). Normal sessions can then be established with the normal targets for I/O operations.
Transport Statistics Transport Statistics Table B-1 Transport Statistics (Continued) iscsiutil Statistic Appendix B CL Description of Field Number of session reopens I The number of time the ioconfigd (I/O Configuration Daemon) initiates a session reopen. Number of session opens in the reopen context I The number of session open requests received in the transport layer while in the reopen context. A reopen is a component of session error recovery.
Transport Statistics Transport Statistics Table B-1 Transport Statistics (Continued) iscsiutil Statistic Number of session state machine transitions to transient state CL I Description of Field The number of session state machine transitions to the transient state. A session enters the transient state when: — The current active connection dies. — Task Management cold reset is in progress. — Session logout has occurred. — Flow control has been enabled.
Transport Statistics Transport Statistics Table B-1 Transport Statistics (Continued) iscsiutil Statistic Appendix B CL Description of Field Number of unexpected events received in session offline state D The number of session state machine unexpected events received while in the offline state. The unexpected events will be ignored, and will not impact operations. If this value is non-zero, an investigation into the cause of the unexpected events should be initiated.
Transport Statistics Transport Statistics 94 Appendix B
C Diagnostic Messages Appendix C 95
Diagnostic Messages Diagnostic Messages Diagnostic Messages The HP-UX iSCSI Software Initiator works with HP-UX Event Monitoring Services (EMS) and the Support Tools Manager (STM). By default, the iSCSI Software Initiator logs all diagnostic messages to the STM log files. STM can be used to view the diagnostic messages logged in the STM log files. EMS can be configured to automatically notify the system administrator when diagnostic messages are logged by the iSCSI Software Initiator.
Diagnostic Messages Diagnostic Messages To change the level of event logging, execute the following command: iscsiutil [/dev/iscsi] -b where dbg_level is one of the level numbers listed in Table C-1, “Logging Levels for the syslog.log File,” on page 96. Logging of events is always turned on. By default, messages at the LVL_ERR and lower levels are displayed in the syslog.log file. Level zero reporting cannot be turned off.
Diagnostic Messages Diagnostic Messages 5. ISCSI_LOG_PROTOCOL_MISSING_TGT_KEY_PART LVL_ERR "The target did not send the remaining portion of the \n" "pair. The partial pair sent in the previous login response \n" "was (%s)." A login key returned by the target is incomplete and, as such, cannot be processed. The specific target login key is included. This information should be provided to HP for analysis. 6.
Diagnostic Messages Diagnostic Messages 11. ISCSI_LOG_PROTOCOL_INIT_KEY_REJECTED LVL_ERR "Initiator login key (%s) was rejected by the target." The initiator login key supplied to the iSCSI target was recognized by the iSCSItarget and then rejected. This information should be provided to the supportteam for analysis. 12. ISCSI_LOG_PROTOCOL_NOTUNDER_ALLOC_FAIL LVL_ERR "Failure to allocate memory to hold a login key (%s) \n" "not understood by the target." An attempt to allocate a buffer failed.
Diagnostic Messages Diagnostic Messages 16. ISCSI_LOG_PROTOCOL_BAD_CKEY_VAL LVL_ERR "Target returned an invalid list response for a login key. \n" "The pair is (%s). The value proposed by the \n" "initiator is (%s)." The target returned a string key value that is invalid. The login failed as a result of protocol violation. This could be because the value does not comply with the result function for that key.
Diagnostic Messages Diagnostic Messages 22. ISCSI_LOG_PROTOCOL_BAD_CHAP_A_VAL LVL_WARN "Invalid value (%s) for the key CHAP_A." An invalid value was returned by the target for the CHAP negotiation key "CHAP_A". 23. ISCSI_LOG_PROTOCOL_BAD_CHAP_I_VAL LVL_WARN "Invalid value (%s) for the key CHAP_I." An invalid value was returned by the target for the CHAP negotiation key "CHAP_I". 24. ISCSI_LOG_PROTOCOL_BAD_CHAP_C_VAL LVL_WARN "Invalid value (%s) for the key CHAP_C.
Diagnostic Messages Diagnostic Messages 30. ISCSI_LOG_SSN_ROUTE_FAIL LVL_ERR "No route found for IP address (%s)." The initiator is not able to reach the specified target address. The specified IP address for the target is changed resulting in no route to the target. Check if the connection between initiator and target is physically secure and established. Check if the target has the same IP address as displayed in the log message.
Diagnostic Messages Diagnostic Messages 37. ISCSI_LOG_TEMP_REDIRECT_REQUESTED LVL_INFO "Login response with status code (0x%x) to" "TargetAddress %s indicated a" "temporary redirection request to %s." During login,an iSCSI target device requested the initiator to perform a temporary login redirection to a new TargetAddress. 38. ISCSI_LOG_PERM_REDIRECT_REQUESTED LVL_INFO "Login response with status code (0x%x) to" "TargetAddress %s indicated a" "permanent redirection request to %s.
Diagnostic Messages Diagnostic Messages 104 Appendix C
D iSCSI Software Interface Driver Statistics Appendix D 105
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Statistics are maintained in the iSCSI Software Interface Driver (SWD). These statistics are explained in Table D-1, “Software Interface Driver Statistics,” on page 107. The Class column (CL) provides message classification. Messages can be informational (I), target errors (T), transient driver errors (D), or connectivity problems (C).
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics iscsiutil Statistic CL Description of Field Software Interface Driver Global Interface Statistics Number of connection opens I The number of TCP connection opens initiated. The statistic is incremented when a call to open a connection is made. Number of connection closes I The number of TCP connection closes initiated.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic 108 CL Description of Field Number of asynchronous failures waiting for a login response D The number of asynchronous failures experienced while waiting for a login response. The asynchronous failure might be due to a PDU exchange timeout/abort or lack of memory resources.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic CL Description of Field Number of target authentication timeouts I/C The number target authentication timeouts that occurred during communication with the userspace iradd daemon. Number of target authentication failures I/C The number of target authentication failures for CHAP.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic 110 CL Description of Field Number of streams message duplication failures D The number of streams message duplication operations that failed. As a result of the failure, the iSCSI Software Initiator will not transmit the related iSCSI commands. The regular occurrence of this event will have a negative impact on performance.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic Appendix D CL Description of Field Number of I/O timeouts D/T The number of SCSI I/Os that did not complete within a time period preset by an upper level protocol (SCSI). The driver will recover from SCSI I/O timeouts using session level error recovery, for example, tearing down the session and starting over.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic CL Description of Field Number of I/Os failed due to an offline connection D The number of SCSI I/Os that were aborted as a result of retrying memory resource allocation when the connection went offline. As a result of this event, the corresponding SCSI I/O will be aborted. This could be a network infrastructure problem.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic Appendix D CL Description of Field Number of Data-In PDUs received without data I The total number of empty Data-In PDUs received by the initiator. Number of invalid R2T PDUs received T The total number of Request to Transfer (R2T) PDUs from the target that had an incorrect buffer offset or Data Transfer Length in them.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic 114 CL Description of Field Number of I/O underflows I The number of I/Os on a connection where the target sent less data than what was requested by the initiator. A large value for this statistic is normal.
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic Appendix D CL Description of Field Number of "target requests logout" Async events received I The total number of times the target sent an asynchronous event with the AsyncEvent set as "target requests logout".
iSCSI Software Interface Driver Statistics iSCSI Software Interface Driver Statistics Table D-1 Software Interface Driver Statistics (Continued) iscsiutil Statistic 116 CL Description of Field Number of Reject PDUs due to Negotiation Resets I The total number of Reject PDUs sent by the target that had the Reason set as "Negotiation Reset". Number of Reject PDUs due to target Waiting for Logout I The total number of Reject PDUs sent by the target that had the Reason set as "Waiting for Logout".
E iSCSI Software Interface Driver Diagnostic Messages Appendix E 117
iSCSI Software Interface Driver Diagnostic Messages iSCSI Software Interface Driver Diagnostic Messages iSCSI Software Interface Driver Diagnostic Messages The HP-UX iSCSI Software Interface Driver works with HP-UX Event Monitoring Services (EMS) and the Support Tools Manager (STM). By default, the iSCSI Software Interface Driver logs all diagnostic messages to the STM log files. STM can be used to view the diagnostic messages logged in the STM log files.
F Glossary This chapter contains definitions of terminology and acronyms used throughout this document.
Glossary Terminology Terminology Directory Agent - A process which collects service advertisements. There can only be one DA present per given host. Discovery Session - Initiated with a Discovery Target to discover Operational Targets in a Network Entity. Gigabit Ethernet - An ethernet infrastructure with the capability of transferring data at the rate of 1 gigabit per second in either the transmit or receive direction (abbreviated GigE).
Glossary Terminology Session - The iSCSI equivalent of a SCSI I-T nexus. A session must be established between an iSCSI initiator and an iSCSI target prior to any communication. Supported - A feature in a release for which implementation and testing for that release have been completed. Target Address - consists of three components, the IP address of the network portal the target uses, its TCP port number, and its target portal group tag.
Glossary Acronyms Acronyms CHAP - Challenge-Handshake Authentication Protocol - A technique to authenticate initiators and targets. DA - Directory Agent - an SLP component. Fibre Channel - an encapsulation protocol used primarily for SCSI on HP-UX. GigE - Gigabit Ethernet - an ethernet network that functions at Gigabit speeds. HA - High Availability - a configuration component designed to maximize hardware and software availability through various component fail-over techniques.
Glossary Acronyms SAM-2 - SCSI Architecture Model (2) - a T10 standard. SAN - Storage Area Network - a network with emphasis on storage with a defined protocol for the infrastructure. SCSI - Small Computer Systems Interface - a mass storage data transmission protocol. SD - Software Distributor - an HP-UX tool for installation and distribution of software. SG - Serviceguard - an HA product for HP-UX. SLP - Service Location Protocol - a standard for local service delivery in an intranet.
Glossary Acronyms 124 Appendix F
Index A aborted reopen sessions, 91 adaptation layer, kernel build, 34 addresses IP, 26, 60, 102 Operational targets, 45, 82, 83 routing failures, 91 alert level syslog message, 96 asynchronous events driver statistics, 108, 114 transport statistics, 91, 92 authentication.
Index Host Bus Adapter (HBA), 25 host systems driver configuration, 74 static Discovery, 26 hostname configuration, 46 iscsi_resolvd daemon, 32, 60 resolution of, 91, 101 hostname resolution daemon (iscsi_resolvd), 32 HP-UX Event Monitoring Services (EMS) See also diagnostics HP-UX iSCSI Software Initiator.
Index See also syslog file messages login failures driver statistics, 107, 108 login negotiation, 65 syslog messages, 98, 118 transport statistics, 93 login keys configuration, 82 syslog messages, 98 types, 41 logouts, tracking, 91, 108 LUNs (logical unit numbers) and hardware path, 25 diagnostic messages, 97 SCSI-3 REPORT LUNs, 89 static Discovery, 26 tracking unclaimed, 90 LVL_ALERT, 96 LVL_CRIT, 96 LVL_DEBUG, 96 LVL_ERR, 96 LVL_INFO, 96 LVL_NOTE, 96 LVL_PANIC, 96 LVL_WARN, 96 M man pages, iSCSI, 32 mass
Index SLP (Service Location Protocol) Discovery, 26, 50 driver specifications, 74 islpd daemon, 32 troubleshooting, 66 SNACK rejects, 115 socket interface, 79 Software Distributor (SD) tool, 32 Software Interface Driver, 78, 118 Software Interface Driver (SWD).
