ICP355I CHANNEL PATH ASSOCIATED WITH CHPID xx IN CSS y HAS zzzzz VALID SUBCHANNELS WHICH EXCEEDS MAXIMUM ALLOWED [FOR {OSN | 3745} DEVICES]

Explanation

You specified too many valid subchannels for channel path xx in CSS y. Valid subchannels are devices which are defined to a logical partition and permitted for use by the logical partition. Valid subchannels are calculated as follows:
  • For unshared channel paths and for reconfigurable FCP channel paths on CPCs without fixed HSA, each device defined in IOCP represents a single valid subchannel. See Table 1 to determine if your CPC has fixed HSA.
  • For reconfigurable FCP channel paths on CPCs with fixed HSA, each FCP device defined in IOCP represents multiple valid subchannels based on the total number of logical partitions (LPs) in its CHPID candidate list.
  • For shared channel paths, each device defined in IOCP represents multiple valid subchannels based on the total number of LPs in its device candidate list.
One of the following conditions exists:
  • You defined too many valid subchannels on an OSH channel path. A maximum of 256 valid subchannels can be defined on an OSH channel path. A valid subchannel for an OSH device can have any unit address in the range 00-FE.
  • You defined too many OSA valid subchannels on an OSD, OSM, or OSX channel path. A maximum of 480 OSA valid subchannels can be defined on an OSD or OSX channel path when priority specification is enabled (CHPARM=00 is specified on CHPID statement). A maximum of 1920 OSA valid subchannels can be defined on an OSD, OSM, or OSX channel path when priority specification is disabled (CHPARM=02 is specified). An OSA subchannel is a device with a unit address in the range 00-FD. The device with unit address FE (OSAD) is excluded from the maximum.
  • You defined too many OSN or 3745 valid subchannels on an OSN channel path. A maximum of 480 OSN valid subchannels and 180 3745 valid subchannels can be defined on an OSN channel path. OSN subchannels are defined with UNIT=OSN on the IODEVICE statement, and 3745 subchannels are defined with UNIT=3745. Valid subchannels are devices with unit addresses in the range 00-FD. The OSAD device with unit address FE is excluded from the maximums
  • You defined too many valid subchannels on an FCP channel path. A maximum of 480 valid subchannels can be defined on an FCP channel path.

System action

IOCP does not complete the generation of an IOCDS and does not produce configuration reports.

Programmer response

For an unshared channel path or reconfigurable FCP channel paths on CPCs without fixed HSA, reduce the number of devices defined on the FCP or OSH channel path or defined on the OSD, OSM, OSN, or OSX channel path with unit addresses in the range 00-FD.

For a reconfigurable FCP channel path on CPCs with fixed HSA, do one or both of the following:
  • Reduce the number of devices defined on the FCP channel path
  • Specify a CHPID candidate list for the FCP channel path with fewer logical partitions.
For a shared channel path, do one or both of the following:
  • Reduce the number of devices defined on the FCP or OSH channel path or defined on the OSD, OSM, OSN, or OSX channel path with unit addresses in the range 00-FD.
  • Specify device candidate lists with fewer logical partitions for the devices defined on the FCP or OSH channel or defined on the OSD, OSM, OSN, or OSX channel path with unit addresses in the range 00-FD. For devices assigned to OSN channel paths, specify device candidate lists that restrict the OSN devices to CCL images and the 3745 devices to operating system images.

For an OSD channel path on an OSA-Express2 or later feature or for an OSM or OSX channel path on an OSA-Express3 or later feature, if you want to disable priority specification to increase the maximum number of valid subchannels available on the channel, specify the appropriate CHPARM keyword value for the OSD or OSX channel path (CHPARM=02).