README file for Microsoft iSNS server and client support, part of the Microsoft iSCSI Initiator product. Copyright (c) 2001 - 2004 Microsoft Corp. All Rights Reserved. ------------------------------------------------------------------------------ ABSTRACT: This readme file briefly describes the caveats, restrictions, and configuration of the Microsoft iSNS Server. It is a working implementation of the iSNS Internet-Draft Revision 22. The current iSNS standard may be obtained at: [http://www.ietf.org/ids.by.wg/ips.html]. Please also see the Microsoft iSNS Server Users Guide for more detailed setup and troubleshooting information. CAVEATS: Currently it is not possible to query for DD related information of a Node or Portal. This will be remedied in a future release. SCNEvent and Heartbeat messages are not currently supported. Use of UDP for communications with the iSNS server is not currently supported. Please use TCP for now. Control Nodes are not supported. The iSNS server must be administered using the provided WMI or CLI or UI interfaces. Index attributes are not currently supported. RESTRICTIONS: The server will enforce a default ESI Interval for Portals that are registered for ESI, and default Registration Period for all Entities. The current defaults for these are 5 minutes for ESI Interval and 15 minutes for Registration Period. Note that if a client supports ESI, then the ESI response is sufficient to refresh the Registration Period, and the client does not need to worry about explicitly refreshing the registration by sending a request to the server. Note that these ESI Interval and Registration Period enforcements are to ensure a dynamic and as up-to-date server database as possible. Allowing clients to have a lengthy ESI Interval or Registration Period would allow stale clients to remain registered for an excessive amount of time in the event that the client is no longer accessible on the network. Also, the DD/DDS related functions have been locked down such that only the WMI interface can manipulate DDs and DDSs. Network clients will not be able to use those functions. IPv6 Notes: The iSNS server supports IPv6. This means that the iSNS server will listen for TCP connections on the IPv4 and IPv6 addresses that are assigned to the server running iSNS. This means that iSNS clients may use IPv4 or IPv6 connectivity and may also specify IPv4 or IPv6 addresses in the attributes passed as part of the iSNS protocol. Connections made by the iSNS server for SCN and ESI will be IPv4 or IPv6 depending upon the type of address passed in the registration message. Note that the iSNS server uses the mechanism described in RFC 2373 for determining if an address is an IPv6 address or a mapped IPv4 address. Mapped IPv4 addresses have 0xFFFF immediately preceeding the IPv4 address in the 16 byte array. | 80 bits | 16 | 32 bits | +--------------------------------------+--------------------------+ |0000..............................0000|FFFF| IPv4 address | +--------------------------------------+----+---------------------+ Care must be taken when using link local addresses. A link local address is an address that is generated locally by the device or computer and is only valid on a specific link. This means that a multihomed device would have multiple link local addresses and the right link local address must be used on the right interface. If the devices on your SAN are multihomed then registering link local addresses may be problemmatic. It is recommended that global addresses are used instead. INSTALLATION AND USAGE: Microsoft iSNS support exists as both server and client implementations. Server support for iSNS is provided in the Microsoft iSNS service, while iSNS client support is provided in the Microsoft iSCSI Initiator service. You will need an iSCSI target that supports iSNS. To install Microsoft iSNS support for iSCSI, there are two main steps: 1) Installation of the Microsoft iSCSI initiators, and iSNS server 2) Configuring the Microsoft iSCSI Initiator to utilize iSNS for iSCSI target discovery purposes Each of these steps is explained in further detail below: 1) Installation of the Microsoft iSCSI initiators, and iSNS server The first step is to install the Microsoft iSCSI initiator support. Please read the appropriate documentation for specific details about the installation of this product. To install the Microsoft iSNS server, merely double-click the iSNS MSI installation program on the machine that you wish to run the iSNS server on, and follow the instructions. Note that running the Microsoft iSNS server is currently supported on machines running Windows 2000, Windows XP, or Windows Server 2003. When the Microsoft iSNS server has been installed, it will be configured to start automatically. It is not necessary to manually start the server. 2) Configuring the Microsoft iSCSI Initiator to utilize iSNS for iSCSI target discovery purposes Note that this step is not necessary if you have a DHCP server that is configured for the iSNS DHCP option and you are running a version of the Microsoft iSCSI initiator with support for the iSNS DHCP option. Please see the DHCP SUPPORT section below for further information. The last real step involves configuring the Microsoft iSCSI Initiator to use iSNS for iSCSI target discovery purposes (in addition to whatever other discovery methods you might already be using). The Microsoft iSCSI Initiator may be configured via the Microsoft iSCSI Initiator user interface, or the ISCSICLI.EXE utility program. To configure the Microsoft iSCSI Initiator to always use iSNS when it is started, you need to "add" the iSNS server to the currently used discovery methods. To add an iSNS server via the user interface, double-click the Microsoft iSCSI Initiator icon on the Windows desktop. Then select the iSNS Servers tab, and click Add. Enter the name or address of the iSNS server, then click OK. To add an iSNS server via the command-line interface, first open a command prompt. Then you would use the ISCSICLI.EXE AddiSNSServer command line parameter. For example, to add the iSNS server "ISNS01", you could use the following command line: ISCSICLI AddiSNSServer ISNS01 The discovery method is updated dynamically, and adding an iSNS server should cause the Microsoft iSCSI discovery service to immediately query the specified iSNS server for the list of available iSCSI targets, which will then be available for immediate use, and you may then list them or login to them, etc. Note that once you have added an iSNS server via either method, it remains persistent, meaning that each time the Microsoft iSCSI Initiator is started again in the future, it will automatically requery the iSNS server for the current list of available targets. Please see the Microsoft iSCSI Initiator documentation for more information on the Microsoft iSCSI Initiator. DHCP SUPPORT: Automatic discovery of the iSNS server is possible via DHCP, if your network has a DHCP server and this DHCP server is configured with the DHCP option for iSNS. If your network has a Microsoft DHCP server, and if the Microsoft iSNS server setup program is being installed by a user with DHCP server administration rights, then the Microsoft iSNS server setup program can automatically configure this option for you. Currently, DHCP option number 43 (Vendor-specific) is being used. The Microsoft iSNS server setup program will attempt to configure the iSNS DHCP option using this option number until the actual number for the iSNS DHCP option is allocated by the IANA. The current specification for the iSNS DHCP option may be obtained at: [http://www.ietf.org/ids.by.wg/dhc.html] EPILOGUE: If you have followed all of the preceding steps correctly, your Microsoft iSCSI system should now be fully operational, using iSNS for iSCSI discovery purposes. Thank you for using the Microsoft iSNS Server. SUPPORT: Support for the Microsoft iSNS Server package is available through Microsoft Product Support Services. For product support options, please see: http://support.microsoft.com