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2.17.3 Improved SAN support (SANCHECK function)
*5 Since the introduction of the fibre channel, the FC connection
*5 technology SAN (Storage Area Network) is being used increasingly
*5 for connecting Symmetrix storage subsystems and magnetic tape de-
*5 vices (CentricStor and LTO). The previous control functions in
*5 BS2000/OSD only allow a limited view of the actually present pe-
*5 ripherals and their connections. If problems occur when mounting
*5 devices or during operation, the cause is often very difficult to
*5 find, e.g. the INOP message from a device may be caused by con-
*5 nection malfunction anywhere in the SAN, but it may also be due
*5 to a generation or wiring error.
*5 The new SANCHECK function supports detecting generation errors
*5 with S and SX servers as well as localizing error conditions in a
*5 SAN.
*5 Generation errors in BS2000, wiring errors or faulty zoning set-
*5 tings are detected by comparing the path generated in BS2000 to a
*5 device with the connections actually present in the SAN. Possible
*5 generation errors are, e.g. wrong specification of the controller
*5 WWPN (World Wide Port Number).
*5 With errors in I/O operation, the error information on the path
*5 between the channel and controller/device and to the FC switch or
*5 fabric is output, thus allowing the error to be localized.
*5 The SANCHECK function is called with the START-SANCHECK command.
*5 The command requires the TSOS command privilege or OPERATING or
*5 SERVICE.
*5 SANCHECK offers the two statements SHOW-SAN-PATH and
*5 SHOW-SAN-CONFIGURATION.
*5 The SAN configuration data is determined with the first command
*5 execution. The data is then used for subsequent call accesses
*5 unless a data update is explicitly requested.
*5 SANCHECK requires the POSIX subsystem since the SAN configuration
*5 data is determined via POSIX-based SNMP interfaces. The SNMP
*5 functions "getmany" used by SANCHECK are provided in the
*5 BS2000/OSD-BC component SNMP-LIGHT and in the product SBA-BS2
*5 (SNMP-Basic-Agent BS2000).
*5 Note
:
*5 With SX servers up to and including SX150, only path and
*5 zoning information can be shown because the X2000 V3.0 carrier
*5 system does not support reading out the BS2000 disk configura-
*5 tion. It is therefore not possible to check the disk configura-
*5 tion against the physical wiring. This function will be offered
*5 for future SX servers with X2000 V4.0.
2.17.4 New functions in POSIX A39
*5 Dynamic modification of POSIX tuning parameters
*5 The control parameters for the POSIX system kernel are stored in
*5 the POSIX parameter file (SYSSSI.POSIX-BC.<version>). Changes to
*5 this parameter file only take effect after the POSIX subsystem is
*5 restarted.
*5 As of POSIX A39, some selected POSIX tuning parameters can be
*5 modified dynamically using the new privileged shell command usp.
*5 If the modified values are also to be valid for the next POSIX
*5 session, they must be entered in the SYSSSI file.