CHPID

CHPID is an optional statement that defines:
  • Channel path identifiers (chpids)
  • Physical channel identifiers (pchids)
  • Channel path types
  • chpid assignment to ESCON and FICON Directors
  • Connecting chpids
  • Channel path parameter
  • I/O cluster name owning a chpid
  • Adapter identifiers (AIDs), ports, and connecting system names
  • Availability of chpids to logical partitions
  • Reconfigurability of chpids among logical partitions
  • Shared chpids for logical partitions
  • Spanned chpids for logical channel subsystems
  • Physical network identifier.
When specified, the CHPID statement must:
  • Follow the ID statement (if specified) and the RESOURCE statement
  • Precede any CNTLUNIT statements that refer to the chpid it defines
  • Collectively, specify all chpids to use in the configuration.

Channel paths not specified in a CHPID statement cannot be used.

See Coding IOCP statements for a summary of the rules for coding statements and the notation in this document to illustrate statements.

The format of the CHPID statement is as follows:
[symbol] CHPID    PATH=(CSS(cssid[,cssid]...),chpid number) 
                  [PCHID=number] 
                  [VCHID=number] 
                  TYPE={CBY | CVC | CNC | CTC | CFP | CFR | CFS |
                        CBP | CBR | CBS | ICP | CIB | CL5 | CS5 | OSC | OSD |  
                        OSE | OSM | OSN | OSX | FC  | FCV | FCP | IQD   }  
                  [MIXTYPE]
                  [SWITCH=number] 
                  [PART | PARTITION={(CSS(cssid),{name|0}[,REC])|
                        (CSS(cssid),access list)|
                        (CSS(cssid),(access list)[,(candidate list)][,REC])|   
                        ((CSS(cssid),(access list)[,(candidate list)]),...)}]
                  [NOTPART={(CSS(cssid),access list)|
                        ((CSS(cssid),(access list)[,(candidate list)]),...)}] 
                  [SHARED] 
                  [PNETID=([,...]physical network id[,...]) 
                  [CPATH=(CSS(cssid),chpid number)] 
                  [CHPARM=value] 
                  [IOCLUSTER=name]    
                  [AID=aid number]    
                  [PORT=number]    
                  [CSYSTEM=name]    
PATH=
cssid
Specifies the logical channel subsystem (CSS) associated with this parameter. A CSS ID is a 1-digit number in the range 0-n. See Table 2 to determine the maximum CSS ID your CPC supports.

The CSS IDs must have been defined in the PART or PARTITION keyword on the RESOURCE statement. You can specify as many CSSs as you defined. If only a single CSS was defined, the CSS parameter is optional.

If you specify multiple CSS IDs for a channel path, IOCP defines the channel path as spanned. A spanned channel path is available for use by the logical partitions in each specified CSS. All channel paths can be spanned except CNC, CTC, CVC, CBY, FCV, CFR, and CBR (TYPE keyword). See Table 1 to determine which channel path types your CPC supports being spanned.
chpid number
Specifies a 2-digit hexadecimal channel path ID (chpid) number for the channel path for each CSS ID specified in the CSS parameter. A chpid cannot be duplicated within a CSS. See Machine limits and rules to determine the valid chpid ranges your CPC supports.
PCHID=number
Specifies the physical channel identification (pchid) number associated with the channel path. The pchid number is a 1- to 3-digit hexadecimal number in the range 0-n where n is the maximum number your CPC supports. See Machine limits and rules to determine the maximum pchid number your CPC supports.

The pchid number identifies the physical location (cage, slot, card port) for a channel path in the CPC. The CPC maintains this mapping. This number can change; for example in ESCON port sparing, if one card port fails, the CPC enables the spare port and assigns the pchid number to the new port.

PCHIDs are generally unique to the card slot, some slots have multiple PCHIDs, some only one. A PCHID on a CHPID statement must not match a PCHID on a FUNCTION statement or the reverse.

The PCHID keyword is not allowed for internal channel paths ICP and IQD (TYPE keyword) and for CIB and CS5 channel paths. The PCHID keyword is required for all other channel path types. PCHID and VCHID keywords are mutually exclusive and only one can be used on a given CHPID statement.

Multiple CL5 channel paths can be specified with the same pchid. You can define a maximum of 8 CL5 channel paths with the same pchid.

The keyword is optional when performing a deck verification. It is required when writing an IOCDS. IOCP can validate an IOCP input file without pchids by performing a deck verification (WRTCDS=NO or NOWRTCDS). You can see the PCHIDs available for the I/O configuration of the CPC on the PCHID Report. (See Using a PCHID report to help plan your I/O configuration.) You can either use the PCHID Report and assign pchid numbers to channel paths or use the CHPID Mapping Tool. The CHPID Mapping Tool is available from Resource Link at www.ibm.com/servers/resourcelink. The tool can use the IOCP input file and add the appropriate pchid numbers for your configuration to the CHPID statements. IOCP can then use the input file to write an IOCDS.
Note: An IOCP input file that HCD created without pchids must be migrated back into HCD after the CHPID Mapping Tool has added pchid numbers to the file. HCD can then write an IOCDS, or a new IOCP input file can then be created from HCD that stand-alone IOCP can use to write an IOCDS.
VCHID=number
Specifies the virtual channel identification (vchid) number associated with the channel path. The vchid number is a 1- to 3-digit hexadecimal number in the range n-m where n is the minimum number and m is the maximum your CPC supports. See Table 2 to determine the minimum and maximum vchid numbers your CPC supports. If no vchid numbers are listed, then the VCHID keyword is not supported on that particular machine.

The vchid number identifies the (virtual) channel path in the CPC. The CPC maintains this mapping.

The VCHID keyword is allowed only for channel path TYPE=IQD (internal queued direct communication (HiperSockets)). The VCHID keyword is required for TYPE=IQD channel paths on CPCs that have a minimum and maximum vchid.

TYPE=
Specifies the mode of I/O operation for the channel path. See Machine limits and rules to determine which channel path types your CPC supports.
CBY
Specifies that the channel path is an ESCON channel that attaches to a 9034 ESCON Converter Model 1 or similar converter. IOCP defines CBY channel paths as parallel channel paths.
CBY channel paths operate the same as parallel byte multiplexer channel paths. They operate in burst mode or byte-interleave mode, depending on the attached control unit.
Notes:
  1. CBY channel paths require ESCON channel hardware.
  2. If you define an ESCON channel as CBY but do not attach it to an ESCON Converter, the channel is put into a permanent standby error state at power-on reset (POR). Put the channel in single channel service mode before POR to avoid the channel error. However, the channel is still unusable until it is attached to an ESCON Converter.
CVC
Specifies that the channel path is an ESCON channel that attaches to a 9034 ESCON Converter Model 1 or similar converter. IOCP defines CVC channel paths as parallel channel paths.
CVC channel paths operate the same as parallel block multiplexer channel paths. They operate only in burst mode and allow multiplexing between blocks. See Figure 1 for CVC channel path coding examples.
Notes:
  1. CVC channel paths require ESCON channel hardware.
  2. If you define an ESCON channel as CVC but do not attach it to an ESCON Converter, the channel is put into a permanent standby error state at POR. Put the channel in single channel service mode before POR to avoid the channel error. However, the channel is still unusable until it is attached to an ESCON Converter.
CNC
Specifies that the channel path is an ESCON channel, and that all control units and I/O devices that attach to this channel path support the ESCON Architecture protocol. See Configuration examples for CNC channel path coding examples.
CTC
Specifies that the channel path is an ESCON channel that permits channel-to-channel communications. See Configuration examples for CTC channel path coding examples.
A CTC channel path communicates with CNC channel paths and, conversely, a CNC channel path communicates with CTC channel paths. A CTC channel path cannot communicate with another CTC channel path, nor can a CNC channel path communicate with another CNC channel path.
Notes:
  1. You must specify identical unit addresses in the CNTLUNIT statements for CTC and CNC channel paths that communicate with each other.
  2. You must specify the MIF image ID or logical partition numbers associated with shared CNC and CTC channel paths in the CUADD keyword on the CNTLUNIT statements for the CTC communication. See ESCON and FICON Channel-to-Channel Reference, SB10-7034, for more information.
  3. When specifying a control unit associated with an unshared CNC and CTC channel path, do not use the CUADD keyword.
CFP
Specifies that the channel path is a coupling facility peer channel. CFP channel paths are defined for ISC-3 links. Each CFP channel path assigned to a control unit should have seven devices defined.

A CFP channel path connects to another CFP channel path.

CFR
Specifies that the channel path is a coupling facility receiver channel. CFR channel paths are defined for ISC-3 links. You can define a CFR channel path only for a coupling facility logical partition to use.

A CFR channel path connects to a CFS channel path. A CFR channel path cannot connect to another CFR channel path.

CFS
Specifies that the channel path is a coupling facility sender channel. CFS channel paths are defined for ISC-3 links. Each CFS channel path should have two devices defined.

A CFS channel path connects to a CFR channel path. A CFS channel path cannot connect to another CFS channel path.

CBP
Specifies that the channel path is an Integrated Cluster Bus coupling facility peer channel. CBP channel paths are defined for ICB-3 and ICB-4 links. Each CBP channel path assigned to a control unit should have seven devices defined.

A CBP channel path connects to another CBP channel path. However, an ICB-3 link must connect to another ICB-3 link and an ICB-4 link must connect to another ICB-4 link.

CBR
Specifies that the channel path is an Integrated Cluster Bus coupling facility receiver channel. CBR channel paths are defined for ICB-2 links. You can define a CBR channel path only for a coupling facility logical partition to use.

A CBR channel path connects to a CBS channel path. A CBR channel path cannot connect to another CBR channel path.

CBS
Specifies that the channel path is an Integrated Cluster Bus coupling facility sender channel. CBS channel paths are defined for ICB-2 links. Each CBS channel path should have two devices defined.

A CBS channel path connects to a CBR channel path. A CBS channel path cannot connect to another CBS channel path.

ICP
Specifies that the channel path is an Internal Coupling facility peer channel. Each ICP channel path assigned to a control unit should have seven devices defined.

An ICP channel path connects to another ICP channel path. You must connect every ICP channel path to another ICP channel path by specifying the CPATH keyword in the CHPID statement. You cannot connect an ICP channel path to itself.

See Defining internal coupling channels (TYPE=ICP) for recommendations on defining ICP channel paths.

CIB
Specifies that the channel path is a coupling over InfiniBand channel. Each CIB channel path assigned to a control unit should have seven devices defined.

A CIB channel path connects to another CIB channel path. You must connect every CIB channel path to another CIB channel path by specifying the CPATH and CSYSTEM keywords in the CHPID statement. You cannot connect a CIB channel path to itself. If a CIB channel path is defined, the LSYSTEM keyword on the ID statement is required.

See Defining coupling over InfiniBand or PCIe-O (TYPE=CIB, TYPE=CL5, or TYPE CS5) channels for more information about defining CIB channel paths.

CL5
Specifies that the channel path is a Coupling Express LR channel. Each CL5 channel path assigned to a control unit should have 32 devices defined but IOCP tests for a minimum of eight.

A CL5 channel path connects to another CL5 channel path. You must connect every CL5 channel path to another CL5 channel path by specifying the CPATH and optionally the CSYSTEM keywords in the CHPID statement. You cannot connect a CL5 channel path to itself. If a CL5 channel path is defined, the LSYSTEM keyword on the ID statement is required

See Defining coupling over InfiniBand or PCIe-O (TYPE=CIB, TYPE=CL5, or TYPE CS5) channels for more information about defining CL5 channel paths.

CS5
Specifies that the channel path is a Coupling Short Reach channel (Integrated Coupling Adapter (ICA SR)). Each CS5 channel path assigned to a control unit should have eight devices defined.

A CS5 channel path connects to another CS5 channel path. You must connect every CS5 channel path to another CS5 channel path by specifying the CPATH and optionally the CSYSTEM keywords in the CHPID statement. You cannot connect a CS5 channel path to itself. If a CS5 channel path is defined, the LSYSTEM keyword on the ID statement is required.

See Defining coupling over InfiniBand or PCIe-O (TYPE=CIB, TYPE=CL5, or TYPE CS5) channels for more information about defining CS5 channel paths.

OSC
Specifies that the channel path is an open systems adapter (OSA) channel that operates as an OSA-Express integrated console controller (OSA-ICC). An OSC channel path provides 3270 sessions that can serve as the system operator or master console for an operating system so you can IPL. An OSC channel path can also connect to TPF through 3215 data streams.

OSA-ICC is supported on all 1000Base-T Ethernet cards and beginning with OSA-Express6S on Gigabit Ethernet cards. If an OSC channel path is specified on any other type of channel hardware, the I/O subsystem flags the channel path with a definition error. Also, a Gigabit Ethernet card can only be used for 3270 sessions beginning with the IBM z15 8561 and OSA-Express6S and can only be used for 3215 data streams beginning with the Licensed Machine Code (LMC) level associated with the IBM z16 3932 and 3931 and OSA-Express7S. Otherwise, the I/O subsystem flags the channel path with a definition error. A channel path with a definition error is unavailable until a dynamic I/O change is made or power-on reset is performed with a new IOCDS to resolve the error.

For more OSC channel path configuration information, see Open Systems Adapter-Express Integrated Console Controller User's Guide, SA22-7990.
Note: Devices assigned to OSC channel paths must be configured on the Support Element before use.
OSD
Specifies that the channel path is an open systems adapter (OSA) channel supporting the Queued Direct I/O (QDIO) architecture. An OSD channel path supports IP applications providing connectivity to Gigabit Ethernet, 10 Gigabit Ethernet, 25 Gigabit Ethernet, 1000Base-T Ethernet, Fast Ethernet, and Token Ring LANs. All OSA channel hardware supports OSD channel paths.

For more OSD channel path configuration information, see Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935.

OSE
Specifies that the channel path is an open systems adapter (OSA) channel that uses non-QDIO architectures. An OSE channel path provides connectivity for all LAN protocols supported by the non-QDIO architecture (1000Base-T Ethernet, Fast Ethernet, and Token Ring LANs). OSE channel paths are supported on OSA-Express and OSA-Express2 features. All OSA channel hardware except Gigabit Ethernet and 10 Gigabit Ethernet support OSE channel paths.

For more OSE channel path configuration information, see Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935.

OSM
Specifies that the channel path is an open systems adapter (OSA) channel providing the interface for the zBX management services. The OSM channel path provides access to the intranode management network (INMN). Only OSA-Express3 or later 1000Base-T Ethernet can support the OSM CHPID type.

For more OSM channel path configuration information, see Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935.

OSN
Specifies that the channel path is an open systems adapter (OSA) channel for network control program (NCP). An OSN channel path supports traffic between an operating system image (for example, z/OS®) and a Communication Controller for Linux® (CCL) image. OSN channel paths are supported on OSA-Express2 and OSA-Express3 features Gigabit Ethernet and 1000Base-T Ethernet.
Note: OSA-Express-4S Gigabit Ethernet features do not support the OSN CHPID type.

For more OSN channel path configuration information, see Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935.

OSX
Specifies that the channel path is an open systems adapter (OSA) channel providing the interface for software to access data on the zBX blades. The OSX channel path provides access to the intraensemble data network (IEDN). Only OSA-Express3 or later 10 Gigabit Ethernet can support the OSX CHPID type.

For more OSX channel path configuration information, see Open Systems Adapter-Express Customer's Guide and Reference, SA22-7935.

FC
Specifies that the channel path is a FICON channel and that all control units and I/O devices that attach to this channel path support the FICON Architecture protocol. All FICON channel hardware supports FC channel paths.
FC channel paths can communicate with each other in channel-to-channel communications. See Configuration examples for an FC channel-to-channel coding example.
Notes on defining FICON CTC communication:
  1. You must specify a control unit type (UNIT keyword) of FCTC for FC channel paths to communicate with each other.
  2. You must specify identical unit addresses in the CNTLUNIT statements for FC channel paths that communicate with each other.
  3. You must specify the CUADD keyword on the CNTLUNIT statements for CTC communication when the remote channel path is a shared FC channel path. If the remote channel path is on a CPC that does not support multiple logical channel subsystems, then the logical address specified must equal the partition number of the logical partition with which you want to communicate. If the remote channel path is on a CPC that does support multiple logical channel subsystems, then the logical address specified must equal the combination of the CSS ID and the MIF image ID of the logical partition with which you want to communicate. (For example, specify CUADD=15 for MIF image ID 5 in CSS 1.) For additional information, see the ESCON and FICON Channel-to-Channel Reference, SB10-7034.
  4. When specifying an FCTC control unit associated with an unshared FC channel path, do not use the CUADD keyword.
FCV
Specifies that the channel path is a FICON channel that attaches to an ESCON Director. IOCP defines FCV channel paths as ESCON channel paths. FCV channel paths operate the same way as ESCON channel paths.
Notes:
  1. FCV channel paths require FICON Express LX channel hardware. If an FCV channel path is specified on any other type of channel hardware, including FICON Express2 LX, the I/O subsystem flags the channel path with a definition error and the channel path is unavailable until a dynamic I/O change is made or power-on reset is performed with a new IOCDS to resolve the error.
  2. If you define a FICON channel as FCV but do not attach it to an ESCON Director, the channel is put into a permanent error state after POR. Put the channel in single channel service mode before POR to avoid the channel error. However, the channel is still unusable until it is attached to an ESCON Director.
FCP
Specifies that the channel path is a FICON channel that operates as a Fibre Channel Protocol channel. All FICON channel hardware supports FCP channel paths. See Fibre Channel Protocol support for more information about FCP channel paths.
IQD
Specifies that the channel path is an internal queued direct communication (HiperSockets) channel. See Defining IQD channels for recommendations on defining IQD channel paths.
MIXTYPE

Specifies that FC and FCP channel path types can be defined on the same FICON adapter. Beginning with the FICON Express16S+ adapter, the two ports on the adapter must both be defined as either FC or FCP. If you define a mixture of channel path types on the adapter, one channel path will be usable while the other channel path will be placed in definition error and be unusable. CPCs that support the FICON Express 16S+ adapter may also have prior FICON adapters that do not have this restriction against mixing channel path types. On these CPCs, IOCP defaults to preventing the mixing of FC and FCP channel path types on an adapter. So if the CPC has any FICON adapters prior to FICON Express 16S+ for which you want to define FC and FCP channels on the same adapter, the MIXTYPE keyword must be specified for at least one of the CHPID statements to permit the channel path type mixture. To determine if your CPC requires the MIXTYPE keyword to mix FC and FCP channel path types for an adapter, see Machine rules.

The MIXTYPE keyword is valid only for FC and FCP channel paths. Also, the MIXTYPE keyword is ignored for the following:
  • If specified for a CPC that does not require the keyword to allow a channel path type mixture
  • If specified for a CPC that does not allow a channel path type mixture.

IOCP determines that channel paths are on the same adapter when their PCHIDs are in the same modulo-4 PCHID slot.

SWITCH=number
Specifies an arbitrary number for the IBM 9032 or 9033 ESCON Director or a FICON Director to which the channel path is assigned. The number can range from 00-FF for a maximum of 256 for each IOCDS. A channel path can be assigned to only one number. A FICON Director cannot have the same switch number as an ESCON Director.

For an ESCON channel path using multiple ESCON Directors, specify the switch number for the director that has dynamic connections for the channel path. For a FICON channel path, always specify the switch number of the entry switch. The entry switch is the switch to which the FICON channel actually connects. The switch number for a FICON Director is not the same as the switch address which is set up by using switch control panels. Whenever possible, try to use the same value for switch numbers and switch addresses to reduce the number of ways a director is known. For more information about defining FICON Directors, see Defining FICON switch configurations.

The SWITCH keyword is required as follows:
  • For channel paths to have dynamic connections through a director
  • For FCV channel paths (TYPE keyword)
  • For managed channel paths (CHPARM keyword with, for example, a value of 01).

The SWITCH keyword is valid only for CBY, CVC, CNC, CTC, FCV, and FC channel paths (TYPE keyword). For ESCON Directors, the SWITCH keyword is valid for CBY, CVC, CNC, CTC, and FCV channel paths. However, CBY and CVC channel paths can have only dedicated connections through an ESCON Director. For FICON Directors, the SWITCH keyword is valid for FC channel paths. See Configuration examples for SWITCH keyword coding examples.

In either of the following cases, the I/O subsystem flags the channel path with a definition error:
  • If you specify the SWITCH keyword for an FC channel path (TYPE keyword) that does not attach to a FICON Director
  • If you do not specify the SWITCH keyword for an FC channel path that does attach to a FICON Director.
The channel path is unavailable until it is attached to or detached from a FICON Director to match the configuration definition and it is varied off and on, or until a dynamic I/O change is made or power-on reset is performed with a new IOCDS to resolve the error.
PART=
PARTITION=
Specifies the availability of chpids to logical partitions. All logical partition names and CSS IDs that you specify must match the ones specified in the RESOURCE statement.

You must specify the PART, PARTITION, NOTPART, SHARED, or IOCLUSTER keyword in every CHPID statement or define the channel path as spanned (PATH keyword). You can specify the PART or PARTITION keyword and the SHARED or NOTPART keywords in the same CHPID statement. However, you cannot specify the PART or PARTITION and NOTPART keywords for the same CSS ID in the same CHPID statement.

Either form of this keyword can be used in a CHPID statement. However, only one form of this keyword can be in each statement.
cssid
Specifies the logical channel subsystem (CSS) ID associated with this parameter. The CSS ID is a 1-digit number in the range 0-n. See Table 2 to determine the maximum CSS ID your CPC supports.

Each CSS ID must have been specified in the PATH keyword for this channel path. You can specify as many CSSs as you specified in the PATH keyword. If only a single CSS ID was specified in the PATH keyword, the CSS parameter is optional. If the channel path is spanned and more than one CSS was specified in the PATH keyword, the CSS parameter is required.

name
Specifies the name of a logical partition (LP) that can access the channel path. The LP name is a 1-8 alphanumeric (0-9, A-Z) character name that must have a nonnumeric first character and must have been defined on the RESOURCE statement. You cannot specify a reserved logical partition (*) or the LMC partition MCS_1.
0
Specifies that no LPs can access the channel path following LP activation for the initial POR of the IOCDS. The zero indicates a null access list.
If you specify a zero without parentheses, you cannot specify a candidate list and you must do one of the following actions:
  • Specify the SHARED keyword for a shared channel path
  • Specify multiple CSS IDs in the PATH keyword for a spanned channel path
  • Specify the REC parameter for a reconfigurable channel path.
access list
Specifies the logical partition (LP) or logical partitions (LPs) in the CSS that have the channel path configured online at LP activation following initial power-on reset (POR) of an IOCDS.

After the initial POR of an IOCDS, PR/SM LPAR retains which LPs have the channel path configured online at LP activation following subsequent PORs of the IOCDS. In this case, the access list used to build an IOCDS might not match the access list PR/SM LPAR retains.

Logical partitions that are not specified in the access list of a shared, spanned, or reconfigurable channel path can access the channel path after POR through channel reconfiguration commands if the LP is specified in the channel candidate list of the path. (See candidate list.

The format of the access list is:
 {name[,name]...|0} 
name
See name.
0
Specifies that no LPs in the CSS accesses the channel path following LP activation for the initial POR of the IOCDS. The zero indicates a null access list.
The following rules apply when specifying the access list:
  • If you specify more than one LP name, IOCP defines the channel path as shared. All channel paths can be shared except CBY, CVC, CFR, and CBR (TYPE keyword).
  • If you specify a zero for a null access list in a CSS, you cannot specify a logical partition name for the same CSS.
  • If you specify either one LP name or a zero (a zero indicates a null access list), the channel path can be shared, reconfigurable, or dedicated (unshared and non-reconfigurable).
  • If you specify a zero as the access list (null access list), you must do one of the following actions:
    • Specify the SHARED keyword for a shared channel path
    • Specify multiple CSS IDs in the PATH keyword for a spanned channel path
    • Specify the REC parameter for a reconfigurable channel path
    • Specify a candidate list consisting of one LP name for a dedicated channel path.
  • An LP name can appear only once in an access list.
candidate list
Specifies the logical partitions (LPs) in the CSS that can access the channel path. LPs that are not specified in a channel candidate list of the path cannot access the channel path.

If you specify a candidate list, you do not need to repeat the LP names specified in the access list. IOCP automatically includes in the candidate list the LP names specified in the access list.

The format of the candidate list is:
{name[,name]...|=} 
name
See name.
=
Specifies that the candidate list for the CSS is identical to its access list.
The following rules apply when specifying the candidate list:
  • You cannot specify an equal sign (=) for a candidate list of the channel path if the access list is zero (0 indicates a null access list).
  • If you do not specify a candidate list for a CSS to which the channel path is assigned and the channel path is shared, spanned, or reconfigurable, the candidate list defaults to all logical partitions defined in each CSS to which the channel path is assigned, excluding reserved logical partitions (*) and the LMC partition MCS_1.
  • If you do not specify a candidate list and the channel path is dedicated, the candidate list defaults to the logical partition specified in the access list.
  • If a dedicated channel path has a zero specified as the access list (null access list), you must specify a candidate list of exactly one LP name.
  • If the candidate list consists of more than one LP name, the channel path must either be shared, spanned, or reconfigurable.
  • An LP name can appear only once in a candidate list.
REC
Specifies that the channel path is reconfigurable. Specifying a channel path as reconfigurable allows it to be dynamically moved between logical partitions (LPs) in a CSS. To move it you use channel reconfiguration commands after power-on reset (POR) is complete.
The following rules apply when specifying the REC parameter for a channel path:
  • The channel path must have an access list of one LP name or zero (0 indicates a null access list).
  • If a candidate list is specified, it must consist of one or more LP names.
  • If the candidate list is not specified, it defaults to all LPs defined in the CSS excluding reserved LPs (*) and the LMC partition MCS_1.
  • You cannot specify:
    • The REC parameter and the SHARED keyword
    • The REC parameter and an access list of more than one LP
    • The REC parameter for a spanned channel path
    • An access list of one LP and a candidate list with an LP other than the one in the access list, unless you specify either the REC parameter or the SHARED keyword or define the channel path as spanned.
    • A zero as the access list (null access list) and a candidate list of two or more LPs, unless you specify either the REC parameter or the SHARED keyword or define the channel path as spanned.
    • A zero as the access list (null access list) and no candidate list, unless you specify either the REC parameter or the SHARED keyword or define the channel path as spanned.
NOTPART=
Specifies the availability of chpids to logical partitions. All logical partition names and CSS IDs that you specify must match the ones specified in the RESOURCE statement.

You must specify the NOTPART, PART, PARTITION, SHARED, or IOCLUSTER keyword in every CHPID statement or define the channel path as spanned (PATH keyword). You can specify the NOTPART keyword and the SHARED, PART, or PARTITION keywords in the same CHPID statement. However, you cannot specify the NOTPART and PART or PARTITION keywords for the same CSS ID in the same CHPID statement.

The NOTPART keyword indicates that the channel path is shared. All channel paths can be shared except CBY, CVC, CFR, and CBR (TYPE keyword).
cssid
Specifies the logical channel subsystem (CSS) ID associated with this parameter. The CSS ID is a 1-digit number in the range 0-n. See Table 2 to determine the maximum CSS ID your CPC supports. If the channel path is spanned and more than one CSS ID was specified in the PATH keyword, the CSS parameter is required.

Each CSS ID must have been specified in the PATH keyword for this channel path. You can specify as many CSSs as you specified in the PATH keyword. If only a single CSS was specified in the PATH keyword, the CSS parameter is optional.

access list
Specifies the logical partitions or partitions in a CSS that do not have the channel path configured online at LP activation after initial power-on reset (POR) of an IOCDS.

IOCP generates an access list for the channel path consisting of all LPs in the CSS not specified in the NOTPART access list. For example, if a CSS has three LPs (LP1, LP2, and LP3) and you specify NOTPART=LP2, IOCP generates an access list containing LP1 and LP3.

After the initial POR of an IOCDS, PR/SM LPAR retains which logical partitions have the channel path configured online at LP activation after subsequent PORs of the IOCDS. In this case, the access list used to build an IOCDS might not necessarily match the access list PR/SM LPAR retains.

Logical partitions that are not specified in the access list of a shared, spanned, or reconfigurable channel path can access the channel path after POR through channel reconfiguration commands if the LP is specified in the candidate list of the channel path. (See candidate list.)

The format of the access list is:
{name[,name]...|0}
name
Specifies the name of a logical partition (LP) that cannot access the channel path. The LP name is a 1-8 alphanumeric (0-9, A-Z) character name. It must have a nonnumeric first character. It must have been defined on the RESOURCE statement. You cannot specify a reserved logical partition (*). You can specify the LMC partition MCS_1 but if you do so you must also specify it in the candidate list so it is excluded from both the access and candidate lists. The MCS_1 partition cannot contain any I/O resources. If you omit specifying the MCS_1 partition in the access list, IOCP automatically excludes it from the access list.
0
Specifies that no LPs in the CSS access the channel path following LP activation for the initial POR of the IOCDS. A zero indicates a null access list.
The following rules apply when specifying the access list:
  • If you specify all LP names in a CSS or a zero, no LPs in the CSS access the channel path following LP activation for the initial POR of the IOCDS. (IOCP generates a null access list.)
  • If you specify a zero for a null access list in a CSS, you cannot specify a logical partition name for the same CSS.
  • If you specify a NOTPART candidate list, you do not need to repeat in the NOTPART access list the LP names specified in the NOTPART candidate list. IOCP automatically excludes from the generated access list the LP names specified in the NOTPART candidate list.

    For example, if a CSS has three LPs (LP1, LP2, and LP3) and you specify NOTPART=((LP2),(LP3)), IOCP generates an access list containing LP1.

  • An LP name can appear only once in an access list.
candidate list
Specifies the logical partitions (LPs) in the CSS that cannot access the channel path.

IOCP generates a candidate list for the channel path consisting of all LPs in the CSS not specified in the NOTPART candidate list. For example, if a CSS has three LPs (LP1, LP2, and LP3) and you specify NOTPART=((LP2),(LP3)), IOCP generates a candidate list containing LP1 and LP2.

LPs that are not in the candidate list IOCP generates cannot access the channel path.

The format of the candidate list is:
{name[,name]...|=}
name
See name.
=
Specifies that the candidate list of the channel path is identical to its access list.
The following rules apply when specifying the NOTPART candidate list:
  • You cannot specify an equal sign (=) for the candidate list of a channel path if the access list is zero (0 indicates a null access list).
  • You cannot specify all LP names in a CSS because doing so generates a null candidate list for the CSS.
  • If you do not specify a candidate list for a CSS to which the channel path is assigned for the NOTPART keyword, the candidate list IOCP generates defaults to all LPs defined in the CSS or CSSs, excluding reserved logical partitions (*) and the LMC partition MCS_1.
  • An LP name can appear only once in a candidate list.
  • If you specified the LMC partition MCS_1 in the access list, you must also specify it in the candidate list so it is excluded from both the access and candidate lists. The MCS_1 partition cannot contain any I/O resources. If you omit specifying the MCS_1 partition in the access and candidate lists, IOCP automatically excludes it from the access and candidate lists.
SHARED
Specifies that the channel path on the CHPID statement is shared. All channel paths can be shared except CBY, CVC, CFR, and CBR (TYPE keyword).

You must specify the SHARED, PART, PARTITION, NOTPART, or IOCLUSTER keyword in every CHPID statement or define the channel path as spanned (PATH keyword).

A shared channel path can be accessed by more than one logical partition (LP) at the same time. Unshared channel paths can be accessed only by a single LP. Although a reconfigurable channel path can be dynamically moved between LPs, only a single LP can access it at any given time.

The following rules apply to shared channel paths:
  • If a channel path has an access list of more than one LP or the NOTPART keyword is specified for it, the channel path defaults to shared.
  • A spanned channel path (PATH keyword) defaults to shared.
  • If you specify SHARED without the PART or NOTPART keywords, the access and candidate lists default to all LPs defined in the CSSs to which the channel path is assigned, excluding reserved logical partitions (*) and the LMC partition MCS_1.
  • You cannot specify:
    • SHARED for reconfigurable channel paths
    • An access list of one LP and a candidate list with an LP (other than the LP in the access list with the PART or PARTITION keyword), without specifying either the REC parameter, the SHARED keyword, or defining the channel path as spanned
    • A zero as the access list (null access list) and a candidate list of two or more LPs with the PART or PARTITION keyword, without specifying either the REC parameter, the SHARED keyword, or defining the channel path as spanned
    • A zero as the access list (null access list) and no candidate list with the PART or PARTITION keyword, without specifying either the REC parameter, the SHARED keyword, or defining the channel path as spanned.
PNETID=(physical-network-id[,...])

Specifies the physical network identifiers (pnetids) associated with the ports on the channel adapter. Each pnetid is a 1-16 alphanumeric (0-9, A-Z) value.

The pnetid in the PNETID keyword is a positional parameter. One to four pnetids can be specified which correspond to the ports on the channel adapter. You can omit one or more pnetids by specifying just a comma for that adapter port position in the keyword value. For example, to only specify the second pnetid for a channel path to be associated with the second port of the adapter, you would specify PNETID=(,pnetid ).

Physical network IDs are used for channel path types OSD and IQD to establish the affinity to a particular physical network. When network connections require two interfaces to be coordinated, as with the 10GB RoCE network function adapter and an associated OSD channel path, the pnetids should match. The network adapters that support the OSD channel path type have up to four ports so four pnetids are supported.

An IQD channel path only uses a pnetid associated with the first port. For IQD channel path types, all PNETID values must be unique.

CPATH=
Specifies the ICP, CIB, CL5, or CS5 channel path to which the channel path being defined is connected.

The CPATH keyword is valid only for ICP, CIB, CL5, and CS5 channel paths (TYPE keyword) and is required for all ICP, CIB, CL5, and CS5 definitions. It specifies the channel path that connects to the ICP, CIB, CL5, or CS5 channel path being defined.

For example, PATH=(FE),CPATH=(FF),TYPE=ICP,... specifies that ICP channel path FE is connected to channel path FF. ICP channel paths are internal channel paths and therefore the connected channel paths exist on the same CPC. CIB, CL5, and CS5 channel paths connect to a CIB, CL5, or CS5 channel path, respectively, on the same CPC or a different CPC.

cssid
Specifies the logical channel subsystem (CSS) ID associated with this parameter. The CSS ID is a 1-digit number in the range 0-n. See Table 2 to determine the maximum CSS ID the connecting CPC supports.

The CSS IDs must have been defined in the PART or PARTITION keyword on the RESOURCE statement of the CPC with the connecting channel path. For both internal and external connections, specify one CSS ID associated with the connecting channel path. If the connecting channel path is spanned, only one CSS ID is specified in this parameter.

If the channel path being defined is spanned, the CSS parameter is required. If only a single CSS ID was specified in the PATH keyword and the connecting channel path has the same CSS ID, the CSS parameter is optional.

chpid number
Specifies a 2-digit hexadecimal number for the connecting chpid number.

The CPATH keyword has extra syntax rules when the connected channel paths belong to the same CPC (that is, they are internal connections). All ICP connections are internal. CIB, CL5, and CS5 connections are internal when the CSYSTEM keyword value matches the LSYSTEM keyword value on the ID statement for the CPC. The following syntax rules apply when specifying the CPATH keyword for internal connections:

  • The channel path specified in the CPATH keyword does not need to be defined before its use in CPATH but must be defined somewhere in the configuration.
  • Channel paths cannot connect to each other if they both have candidate lists with the same, single logical partition. This restriction prevents the definition of ICP and internally connected CIB, CL5, or CS5 channels in a configuration with only one logical partition.
  • An ICP, CIB, CL5, CS5 channel path must connect to another channel path of the same type and can connect to only one path.
  • A channel path cannot connect to itself.
  • Connecting two CIB or CS5 channel paths that have the same AID and port is not supported. Also, connecting two CL5 channel paths that have the same PCHID and port is not supported. IOCP does not allow these types of configuration.
CHPARM=value
Specifies a parameter for the channel path that indicates how the channel is to operate. The value is a 2-digit hexadecimal number.

The CHPARM keyword identifies a channel path to be managed by dynamic CHPID management. When bit 7 of the CHPARM value is on (for example, X'01'), the channel path is managed. Only CNC, FCV, and FC channel paths (TYPE keyword) can be managed. A managed channel path cannot be spanned (PATH keyword). Managed paths require that the IOCDS to be dynamic-capable (TOK keyword). A dynamic-capable IOCDS is built when using HCD on z/OS or VM or when calling the IOCP CMS utility with privilege class B for VM.

The CHPARM keyword also specifies whether an OSD or OSX channel path is to disable priority specification. When bit 6 of the CHPARM keyword value is on (for example, X'02'), the OSD or OSX channel path has priority specification disabled and the channel supports a maximum of 1920 OSA valid subchannels (640 TCP/IP stacks). Otherwise, the OSD or OSX channel path has priority specification enabled, and the channel supports a maximum of 480 OSA valid subchannels (160 TCP/IP stacks). OSM channel paths default to disabled priority queuing, and that is the only mode supported for OSM CHPIDs.

Disabling priority specification is supported only for OSA-Express2 or later features. If it is disabled for an OSA-Express feature, the I/O subsystem flags the channel path with a definition error. The channel path is unavailable until a dynamic I/O change is made or a power-on reset is performed with a new IOCDS to resolve the error. For additional information, see I/O configuration considerations.

The CHPARM keyword also specifies the TCP/IP maximum transmission unit (MTU) and the IQDIO frame size to use for I/O requests on IQD channel paths (TYPE keyword). Bits 0 and 1 of the CHPARM keyword value are used and support the following values for IQD channel paths:

  • 00 for 8 K MTU and 16 K frame size
  • 40 for 16 K MTU and 24 K frame size
  • 80 for 32 K MTU and 40 K frame size
  • C0 for 56 K MTU and 64 K frame size.

On 2817 and 2818 with enabling MCL applied or 2828, 2827, or later processors, the following CHPARM values are provided for HiperSocket IQD channel paths (TYPE keyword):

  • 0x for 8 KB MTU and 16 KB frame size
  • 4x for 16 KB MTU and 24 KB frame size
  • 8x for 32 KB MTU and 40 KB frame size
  • Cx for 56 KB MTU and 64 KB frame size
  • x0 for a normal HiperSocket channel path
  • x2 for a HiperSocket for IEDN channel path. You can specify a CHPARM value of x2 for only one IQD channel path.
  • x4 for a HiperSocket capable to be externally bridged channel path

The CHPARM keyword also specifies whether an OSC channel path is to connect to TPF through 3215 data streams. When the required RPQ is installed on your CPC and bit 1 of the CHPARM value is on (for example, X'40'), the channel path can connect to TPF using 3215 data streams. Otherwise, the OSC channel path supports TN3270E emulator sessions.

Any undefined value is incorrect for all channel path types.

The following table summarizes the supported CHPARM values:

Table 1. Supported CHPARM values
CHPARM value CHPID type
CNC, FCV, FC OSC OSD, OSX OSM IQD All others
00 Not Managed TN3270E Priority Enabled Warning. Defaults to priority disabled 8 K MTU N/A
01 Managed Error Error Error Error Error
02 Error Error Priority Disabled Priority Disabled 8 K MTU; IEDN Error
04 Error Error Error Error 8 K MTU; ext bridge Error
40 Error 3215 data streams Error Error 16 K MTU Error
42 Error Error Error Error 16 K MTU; IEDN Error
44 Error Error Error Error 16 K MTU; ext bridge Error
80 Error Error Error Error 32 K MTU Error
82 Error Error Error Error 32 K MTU; IEDN Error
84 Error Error Error Error 32 K MTU; ext bridge Error
C0 Error Error Error Error 56 K MTU Error
C2 Error Error Error Error 56 K MTU; IEDN Error
C4 Error Error Error Error 56 K MTU; ext bridge Error
IOCLUSTER=name
Specifies an I/O cluster name. An I/O cluster is a sysplex that owns a managed channel path (CHPARM keyword). The I/O cluster name is a 1-8 alphanumeric (0-9, A-Z) or special (@, #, or $) character name. The maximum number of I/O cluster names is 64 or 128. See Machine limits to determine the maximum number of I/O cluster names your CPC supports.

Only operating systems running in logical partitions (LPs) that belong to the specified sysplex can manage the channel path.

The IOCLUSTER keyword must be specified for every managed channel path. The IOCLUSTER keyword cannot be specified for any channel path that is not managed.

The PART, PARTITION, and NOTPART keywords cannot be specified on the CHPID statement when the IOCLUSTER keyword is specified. Also, the IOCLUSTER keyword indicates that a channel path is shared and assigns the channel path a null access list and a candidate list of all LPs defined in the configuration including reserved LPs (*) but excluding the LMC partition MCS_1.

AID=aid number
Specifies the adapter identifier (aid) associated with the host channel adapter (HCA) or Integrated Coupling Adapter (ICA) on which this channel path is defined. The aid is a one- to 2-digit hexadecimal number. See Table 2 to determine the aid range your CPC supports.

The aid is determined from the PCHID Report when you order an HCA or ICA (see Using a PCHID report to help plan your I/O configuration) and from Hardware Management Console windows.

The AID keyword is valid only for CIB and CS5 channel paths (TYPE keyword) and is required for all CIB and CS5 definitions. Multiple CIB or CS5 channel paths can be specified with the same aid. You can define a maximum of 16 CIB channel paths or 8 CS5 channel paths with the same aid.

PORT=number
Specifies the port on the host channel adapter (HCA), Coupling Express (CE LR) adapter, or Integrated Coupling Adapter (ICA) to which this channel path is defined. The port number is a 1-digit decimal number in the range 1-n where n is the maximum number of HCA, CE LR, or ICA ports your CPC supports. See Table 1 and Table 2 to determine the maximum port numbers your CPC supports.

The PORT keyword is valid only for CIB, CL5, and CS5 channel paths (TYPE keyword) and is required for all CIB, CL5, and CS5 definitions. Multiple CIB and CS5 channel paths can be specified for the same port on an AID. Multiple CL5 channel paths can be specified for the same port on a PCHID.

CSYSTEM=name
Specifies the name of the system that connects to this channel path. The name is a 1-8 alphanumeric (0-9, A-Z) name.

For a coupling facility connection to be established, the specified CSYSTEM keyword value must match the LSYSTEM keyword value for the CPC with the target CIB, CL5, and CS5 channel path.

The CSYSTEM keyword is valid only for CIB, CL5, and CS5 channel paths (TYPE keyword) and is required for all CIB definitions. The CSYSTEM keyword is optional for CL5 and CS5 definitions.

You cannot connect two CIB, CL5, or CS5 channel paths to the same destination channel path. That is, you cannot specify the same CSYSTEM and CPATH keyword values for two CIB, CL5, or CS5 channel paths.