I/O device report

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The I/O Device Report lists the I/O devices defined in the IOCDS. Devices are reported by the type of control unit to which they attach. Within a group of devices that attach to the same type of control unit, devices are sorted by device number. All the devices defined by the same IODEVICE statement are reported together. For each IODEVICE statement, the report shows the following:
  • Device numbers of the devices
  • Subchannel set IDs in which the devices are defined
  • Unit address of the devices
  • Device type and model
  • CSS IDs to which the devices have access
  • Physical control unit numbers associated with the CSS ID and to which the devices are attached
  • Paths that attach to the physical control unit
  • Switch number associated with the channel path
  • MIF image ID numbers of logical partitions which the channel path can access
  • Any comments for the devices.

Figure 1 shows an example of the I/O Device Report.

If a device is in a subchannel set other than 0, the DEVICE NUMBERS report column for the appropriate CSSs contains (n). The n represents the appropriate subchannel set number. If a device is in subchannel set 1 for a CSS, the DEVICE NUMBERS report column for the appropriate CSSs contains (1). For devices in subchannel set 0 for a CSS, no special indication is present.

The path listed is the composite path that the CPC uses when communicating with the device. This composite path (chpid.link.cuadd) includes the channel path, the link address, and the control unit logical address. If you do not specify LINK but you do specify CUADD, two asterisks (**) are displayed for LINK. If a control unit is managed (PATH keyword on CNTLUNIT statement), two asterisks (**) are displayed for the path.

If the SWITCH keyword is not allowed for the channel path type, the report column contains N/A. If the SWITCH keyword is allowed but not specified for a channel path, the report column contains NONE. If the control unit path is a managed path (PATH keyword on CNTLUNIT statement), the report column contains YES

The MIF IMAGE ID NUMBERS report column shows the MIF image ID numbers of logical partitions which the channel path can access. The following information is reported:
  • For each partition in the access list of the channel path, the MIF image ID column contains an A for the corresponding partition.
  • For each partition in the candidate list but not the access list of the channel path, the MIF image ID column contains a C for the corresponding partition.
  • For all partitions not in the access or candidate lists of channel path, the corresponding MIF image ID columns are left blank.
You can use the PART, PARTITION, or NOTPART keyword in the IODEVICE statement to define a device candidate list that includes or excludes LP access at the device level. The following information is reported in the MIF IMAGE ID NUMBERS report column for a device candidate list:
  • For the first report line for a device, the MIF image ID column contains an asterisk (*) for each partition in the device candidate list.
  • A minus sign (-) for an LP indicates that the device candidate list excludes LP access to the device even though the LP has access to a channel path assigned to the device.
  • A plus sign (+) for an LP indicates that the device candidate list includes LP access to the device even though the LP currently does not have access to a channel path assigned to the device. The LP can access only the device following a dynamic I/O configuration change that adds the LP to the candidate list of the channel path.
Notes:
  1. For each device that has a plus sign (+) in the MIF IMAGE ID NUMBERS column, ensure that you specified the correct LPs in the PARTITION or NOTPART keyword on the IODEVICE statement. The device does not have access to those LPs, even though the channel path does have access, until a dynamic I/O configuration change is made.
  2. If the device has a device candidate list that is equivalent to the one it would have for a default, a plus sign (+) is not shown for LPs included in the device candidate list. A plus sign (+) is shown only if the device candidate list was specified, is not equivalent to the default one, and included an LP for which the path does not have access.
The COMMENT report column contains information that applies to the devices. The following information is reported:
  • STADET if the device has value STADET=Y
  • TIMEOUT if the TIMEOUT keyword is not ignored for the device and has value TIMEOUT=Y
  • Protocol value if the PROTOCL keyword is not ignored for the control units attached to the device as follows:
    • DCI for PROTOCL=D
    • DS-3.0 for PROTOCL=S
    • DS-4.5 for PROTOCL=S4
  • TYPE value of 1 or 2 if the SHARED keyword is not ignored for the control units attached to the device
  • PREFERRED PATH if the channel path is the preferred channel path for the device
  • MANAGED PATHS (x) if the control unit attached to the device has managed paths and where x is the number of managed paths in the control unit.

A legend at the end of the I/O Device Report describes the entries in the MIF IMAGE ID NUMBERS report column.