Defining an OSA-Express device to z/OS Communications Server using QDIO

To define an OSA-Express device to z/OS® Communications Server using queued direct I/O (QDIO), first you need to define a QDIO transport resource list element (TRLE). This is shown in the following example.

TRLHYDRA VBUILD TYPE=TRL                                           
*******************************************************************
*  TRANSPORT RESOURCE LIST FOR OSA-EXPRESS                         
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*        10    16                                                  
HYD1     TRLE  LNCTL=MPC,                                              *
               READ=(2EC0),                                            *
               WRITE=(2EC1),                                           *
               MPCLEVEL=QDIO,                                          *
               DATAPATH=(2EC2,2EC3),                                   *
               PORTNAME=(HYD1G1),                                      *
               PORTNUM=1

In this example, MPCLEVEL=QDIO indicates that the direct I/O interface is used. Control data is transmitted across the one READ and one WRITE device. Normal data is transmitted across a DATAPATH device, where each ULP is assigned its own channel unit address. If you define multiple VLANs to the same OSA, you need to configure a separate INTERFACE definition in TCP/IP for each VLAN and a separate DATAPATH device is needed for each of these interfaces. When MPCLEVEL is QDIO, HPDT MPC is also used for this connection across the control channels. The port number (PORTNUM) specifies which physical port on an OSA-Express is to be used for this QDIO device. For OSA-Express and OSA-Express2, only one port, port number zero, is supported for each CHPID. For OSA-Express3 or later, multiple ports are supported on each CHPID. Within a single logical partition (LPAR), each port must have its own unique TRLE definition, with unique read, write, and datapath channel unit addresses. The port name (PORTNAME) is the name that will be assigned to this port. All z/OS LPARs sharing the same port of an OSA-Express must define the same PORTNAME and PORTNUM on their TRLE definitions representing that OSA-Express port.

See z/OS Communications Server: SNA Resource Definition Reference for more information about coding a TRLE statement.

To define the OSA for IPv4, you must next define either a DEVICE and LINK statement or an INTERFACE statement in your TCP/IP profile. This is illustrated in the following example.

DEVICE HYD1G1 MPCIPA
LINK LHYDRA IPAQENET HYD1G1

In this example, HYD1G1 is the name of the device. The device name must be the port name as defined in a TRLE for a QDIO connection. IPAQENET defines an IPv4 Ethernet interface.

INTERFACE QDIOINTF4 IPAQENET PORTNAME HYD1G1

In this example, the PORTNAME value (HYD1G1) must be the port name in the TRLE definition. IPAQENET defines an IPv4 Ethernet interface.

To define the OSA for IPv6, you need an INTERFACE statement in the TCP/IP profile. This is illustrated in the following example.

INTERFACE HYD1G16 DEFINE IPAQENET6 PORTNAME HYD1G1

In this example, the PORTNAME value (HYD1G1) must be the port name in the TRLE definition. IPAQENET6 defines an IPv6 Ethernet interface.

See z/OS Communications Server: IP Configuration Reference for more information about coding the DEVICE, LINK, and INTERFACE statements.

To continue defining an OSA-Express device, perform the following steps:

Configure and vary the physical devices online.
Activate the TRL deck.
Define and start the device or interface, or both, using TCP/IP.

Note: Datapath channels for OSA-Express should not be varied offline while VTAM® is active.

When z/OS Communications Server participates in an ensemble environment, QDIO TRLE definitions are dynamically generated for connectivity to the intraensemble data network (IEDN) (CHPID type OSX) if the QDIO interface is defined with CHPIDTYPE OSX and the CHPID parameter. For each dynamic TRLE for OSX, the TRLE name is IUTXT0xx and the corresponding port name is IUTXP0xx (where xx is the configured CHPID parameter). QDIO TRLE definitions are also dynamically generated for connectivity to the intranode management network (CHPID type OSM) if OSM CHPIDs are configured. VTAM searches for two OSM CHPIDs when the TCP/IP stack is initialized, and dynamically generates a TRLE for each CHPID. The TRLE names are IUTMT0xx and the corresponding port names are IUTMP0xx, where xx is the OSM CHPID that is found. See Resources automatically activated by VTAM for more information about the naming convention of these TRLEs and the number of DATAPATH devices that are dynamically defined.

Tip: If the values that are chosen for the dynamically created OSX TRLE definitions do not suit your needs (for example, you need more than 17 DATAPATH devices), you can define your own QDIO TRLE and configure the QDIO interface with the PORTNAME parameter. See INTERFACE -- IPAQENET OSA-Express QDIO interfaces statement and INTERFACE -- IPAQENET6 OSA-Express QDIO interfaces statement in z/OS Communications Server: IP Configuration Reference for more information.

Restrictions:

If the QDIO interface that is used for connectivity to the intraensemble data network is defined with the PORTNAME parameter, you must define a QDIO TRLE definition. The PORTNAME parameter value on the TRLE definition must match the PORTNAME parameter value. For information about restrictions on the TRLE name, see Transport resource list major node in z/OS Communications Server: SNA Resource Definition Reference.
If z/OS Communications Server runs as a guest on z/VM® and guest LAN definitions is used for connectivity to the intraensemble data network, you must define the QDIO interface with the PORTNAME parameter.

QDIO TRLE definitions are always dynamically generated for connectivity to the intranode management network (CHPID type OSM). For each dynamic TRLE for OSM, the TRLE name is IUTMT0xx and the corresponding portname is IUTMP0xx (where xx is the value of the OSM CHPID). See TCP/IP in an ensemble in z/OS Communications Server: IP Configuration Guide for more information.