Channel path

A channel path is specified with the CHPID statement. For an XMP processor, a spanned CHPID is defined for one or more channel subsystems. Therefore, the CHPID statement must contain the appropriate channel subsystem ID(s). If only one CSS is defined, it is not required to specify its ID on the PATH keyword.

The CHPID statement contains the following keywords:

PATH

Specifies the CHPID number and, if required, the CSS IDs of the channel path (mandatory).

PNETID

Identifies the physical networks to which the channel path is assigned (optional, only for channel paths of type IQD or OSD).

TYPE

Specifies the channel path type of I/O operation for the channel path (mandatory).

SHARED

Specifies that the channel path on the CHPID statement is shared (optional).

REC

Specifies that the channel path on the CHPID statement is reconfigurable (optional).

PART, PARTITION, or NOTPART

PART and PARTITION specify the access list of logical partitions that will have the channel path configured online after POR, and the candidate list identifying the logical partitions which can access the device.

NOTPART specifies the access list of logical partitions that will not have the channel path configured online after POR, and the list of logical partitions which cannot access the device.

REC

REC in the PART or PARTITION keyword allows the channel path to be dynamically moved between partitions after POR.

CHPARM, OS

Specifies channel path data that is used by the operating system. Examples:

• CHPARM=00 is the default.
• CHPARM=01 indicates that the channel path is managed by DCM.
• CHPARM=02 indicates
  • for IQD channels: channel can access the IEDN (IQDX function)
  • for OSD, OSM, and OSX channels: priority queuing is disabled.

    For OSM channel paths, device priority queuing needs to be disabled. Therefore, for these CHPIDs, HCD converts a CHPARM=00 (default with priority queuing enabled) to CHPARM=02.

• CHPARM=40 indicates that the maximum frame size for an IQD channel is 24K.

For more information about the CHPARM parameter, refer to the IOCP User's Guide for your processor.

I/O CLUSTER

Specifies an I/O cluster name. An I/O cluster is a sysplex that owns a managed channel path for an LPAR processor configuration.

SWITCH

Specifies a number for a switch which is used as a dynamic switch for all paths from the channel path (CHPID) to the connected control units (required for dynamic connections through a switch).

DESC

Specifies a description of the channel path (optional).

TPATH

Specifies a connected CF channel path (optional).

The TPATH parameter can be specified for a CF channel path, either CF receiver, CF sender, or CF peer channel path.

For a CF sender or CF receiver channel path, the TPATH parameter must contain:

• the target processor
• the target CSS ID for XMP processors
• the target channel path ID
• when specified with a CF sender channel path ID, the TPATH parameter must also contain the CF sender control unit and device numbers used for the CF connection (optional for a CF receiver channel paths)

For a CF peer channel path, the TPATH parameter contains the following items for the target and source channel paths of the CF connection:

• the target/source processor
• the target/source CSS ID for XMP processors
• the target/source channel path ID
• control unit number (only if this is a sending CF channel, that is, the channel path connects to a target CF logical partition)
• starting device number (only if this is a sending CF channel)

A CF connection uses two (CF sender channel) or seven (sending CF peer channel) devices. Only the starting one can be specified (with four digits). The remaining devices are automatically assigned to the next consecutive device numbers.

Any CF control units and CF devices specified via CNTLUNIT and IODEVICE statements are ignored.

The connection can only be established if the target channel path exists. If the target channel path is already connected, the existing connection is broken and a new connection is established.

SWPORT

Specifies an entry switch port (optional).

PCHID

Specifies a physical channel identifier (optional).

VCHID

Specifies a virtual channel identifier (optional). Used for internal channel path - exclusiv to the PCHID keyword.

AID

Specifies the ID of the host communication adapter (HCA) on which the channel is defined.

PORT

Specifies the port on the HCA or PCHID on which the channel is defined.

MIXTYPE

Specifies that the channel path resides on an adapter card with a mixture of FC and FCP channel paths. HCD ignores this keyword during migration. For details on when it is allowed/required by IOCP, see the IOCP User's Guide.

PATH=[(CSS(n,…),]chpid_number[)]

PNETID=(pnetid1,…,pnetid4)

TYPE=type

SHARED

REC

For XMP processors:
PART[ITION]=((CSS(0),(acc_lp1,...,acc_lpn)
             [,(cand_lp1,...,cand_lp2)][,REC])
             ...
             [(CSS(n),(acc_lp1,...,acc_lpn)
             [,(cand_lp1,...,cand_lp2)][,REC])]
            )

For SMP processors:
PART[ITION]=((acc_lp1,...,acc_lpn)
             [,(cand_lp1,...,cand_lp2)][,REC]
            )

For XMP processors:
NOTPART=((CSS(0),(acc_lp1,...,acc_lpn)
         [,(cand_lp1,...,cand_lp2)])
         ...
         [(CSS(n),(acc_lp1,...,acc_lpn)
         [,(cand_lp1,...,cand_lp2)])]
        )
For SMP processors:
NOTPART=((acc_lp1,...,acc_lpn)
         [,(cand_lp1,...,cand_lp2)]
        )

OS=xx, CHPARM=xx

IOCLUSTER=sysplex

SWITCH=xx

DESC='description'
 

TPATH=(proc,chpid[,CFS CU,CFS device])
(for legacy CF channel path only)

TPATH=((proc,chpid[,CFP CU,CFP device]),
(proc,chpid[,CFP CU,CFP device]))
(for CF peer channel path only)

TPATH=((CSS(n),proc,chpid[,cu,device]),…)

SWPORT=((swid,port))

PCHID=xxx

VCHID=xxx

AID=xx

PORT=n