draid(4)                                                           draid(4)

NAME
     draid - database for the daemon that monitors both channels of a RAID
     box (Dual RAID Channel Daemon)

DESCRIPTION
     The file /etc/draid contains a list of RAID boxes and their controll-
     ers to be used by draidd(1M). Each entry for a RAID box is an indivi-
     dual line in the following format:

     Dual-RAID-name :
     Number-of-controllers :
     First-controller-device-node  : LUNs-of-first-controller :
     Second-controller-device-node : LUNs-of-second-controller :

     The fields must be separated by ":" (colon). A "#" (hash sign) in the
     first column of a line denotes a comment line. All characters to the
     end of the line are not interpreted by functions that read this file.

     Dual-RAID-name
          The name of a valid virtual RAID device. This name is used in
          subsequent accesses to the RAID box.

     Number-of-controllers
          The number of controllers linked to the RAID box. Two controllers
          are supported at present.

     First-controller-device-node
          The name of the first physical host controller which is connected
          to a RAID box controller.

     LUNs-of-first-controller
          The LUN(s) to be used by the first controller. The various dif-
          ferent LUN(s) are given as decimal numbers separated by blanks.

     Second-controller-device-node
          The name of the second physical host controller which is linked
          to a RAID box controller.

     LUNs-of-second-controller
          The LUN(s) to be used by the second controller. The various dif-
          ferent LUN(s) are given as decimal numbers separated by blanks.














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draid(4)                                                           draid(4)

EXAMPLES
     draid0  :  2 : ios0/sraid030    : 1 2      : ios0/sraid051    : 0 3

          The RAID box is connected to the host over the host controllers
          /dev/ios0/sraid030 and /dev/ios0/sraid051.

          The host controller ios0/sraid030 uses the LUNs one (1) and two
          (2).

          The host controller ios0/sraid051 uses the LUNs zero (0) and
          three (3).

          Applications can access this RAID box over the device nodes
          /dev/draid/draid0lLUNsPARTITION. In this case, LUN must be a
          number between zero and three and PARTITION must be a number
          between zero and 15.

          For example, /dev/draid/draid0l0s0 (LUN: 0, Partition: 0) must be
          mounted after /mnt0, and /dev/draid/draid0l1s2 (LUN: 1, Parti-
          tion: 2) must be mounted after /mnt1. Each access to the file
          system mounted on /mnt0 uses /dev/ios0/sraid051 as an access con-
          troller. If, for any reason, ios0/sraid051 should fail,
          draidd(1M) then directs any further access to /mnt0 to the con-
          troller ios0/sraid030, without involving the system administra-
          tor.

NOTES
     draidd(1M) reads and interprets /etc/draid at startup or after it
     receives the hangup signal (SIGHUP). When draidd(1M) is started the
     controller is not configured, as described in /etc/draid, by default.
     However, the current configuration is read out from the RAID box con-
     troller and the system driver is set with these values. This confi-
     guration may deviate from that described in /etc/draid. However,
     draidd(1M) requires Dual-RAID-name to enable access to the RAID box.
     Should draidd(1M) receive a SIGHUP signal, it attempts to configure
     the RAID box, as described in draid.

     The start procedure is required if a controller is defective at
     startup, and the corresponding RAID box was reconfigured during a pre-
     vious run of draidd(1M). It is also possible in a multihost environ-
     ment that a RAID box was configured by another host. In this case, the
     actual host must assume the configuration of the removed host.

FILES
     /etc/draid

SEE ALSO
     draidd(1M), draid(7).






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