Bridging and IBM Networking Configuration Guide, Cisco IOS Release 15S

Overview of CSNA and CMPC
- Cisco SNA Environments
- Cisco Multipath Channel Environments
Preparing to Configure CSNA and CMPC
- Hardware and Software Requirements
  - Router Requirements
  - Mainframe Requirements
- Mainframe Host Configuration Considerations
  - Defining the Channel Subsystem for the Router
  - Disabling the Missing Interrupt Handler
CSNA Support Configuration Task List
CSNA Verification Configuration Task List
CMPC Support Configuration Task List
CMPC Verification Configuration Task List
Monitoring and Maintaining CSNA and CMPC
- Monitoring Interface Status
- Clearing Counters for CSNA and CMPC
CSNA and CMPC Configuration Examples

Configuring CSNA and CMPC

Cisco SNA (CSNA) and Cisco Multipath Channel (CMPC) are software features that enable a Cisco router to establish channel connections with a mainframe host. This chapter provides information about configuring the Cisco SNA (CSNA) and Cisco Multipath Channel support on the CIP and CPA types of CMCC adapters on a Cisco router.

This information is described in the following sections:

•Overview of CSNA and CMPC

•Preparing to Configure CSNA and CMPC

•CSNA Support Configuration Task List

•CMPC Support Configuration Task List

•Monitoring and Maintaining CSNA and CMPC

•CSNA and CMPC Configuration Examples

For a complete description of the CSNA and CMPC commands in this chapter, refer to the "CSNA, CMPC, and CMPC+ Commands" chapter of the Cisco IOS Bridging and IBM Networking Command Reference (Volume 2 of 2). To locate documentation of other commands that appear in this chapter, use the command reference master index or search online.

To identify the hardware platform or software image information associated with a feature, use the Feature Navigator on Cisco.com to search for information about the feature or refer to the software release notes for a specific release. For more information, see the "Identifying Platform Support for Cisco IOS Software Features" section on page lv in the "Using Cisco IOS Software" chapter.

Overview of CSNA and CMPC

This section provides an overview of the architectural and implementation considerations when configuring a CIP or CPA adapter for connection to a mainframe host using the Cisco SNA or Cisco Multipath Channel features. The following topics are included in this section:

•Cisco SNA Environments

•Cisco Multipath Channel Environments

Cisco SNA Environments

The CSNA feature provides support for Systems Network Architecture (SNA) protocols to the IBM mainframe from Cisco 7500, Cisco 7200, and Cisco 7000 with RSP7000 series routers, using CMCC adapters (over both ESCON and parallel interfaces). As an IBM 3172 replacement, a CMCC adapter in a Cisco router supports the External Communications Adapter (XCA) feature of the Virtual Telecommunications Access Method (VTAM).

Support for the XCA feature allows Logical Link Control (LLC) downstream physical units (PUs) to be defined as switched devices. XCA support also allows the CMCC adapter to provide an alternative to front-end processors (FEPs) at sites where the Network Control Program (NCP) is not required for SNA routing functions.

The CSNA feature supports communication between a channel-attached mainframe and the following types of devices attached to a LAN or WAN:

•Physical Unit (PU) 2.0 SNA node

•PU 2.1 SNA node

•PU 5/4 SNA node

CSNA also supports communication between two mainframes running VTAM that are either channel-attached to the same CMCC adapter card, or channel-attached to different CMCC adapter cards.

The CSNA feature provides SNA connectivity through a Media Access Control (MAC) address that is defined on an internal adapter in a CMCC. The internal adapter is a virtual adapter that emulates the LAN adapter in an IBM 3172 Interconnect Controller. Each internal adapter is defined in a corresponding XCA major node in VTAM, which provides an access point (LAN gateway) to VTAM for SNA network nodes.

The internal adapter is configured on an internal (virtual) Token Ring LAN located in the CMCC. Each CMCC can be configured with multiple internal Token Ring LANs and internal adapters. Each internal Token Ring LAN must be configured to participate in source-route bridging to communicate with the LAN devices attached to the router.

By providing Cisco Link Services (CLS) and the Logical Link Control type 2 (LLC2) protocol stack on the CMCC adapter card, all frames destined to or from the CMCC adapter card are switched by the router. The presentation of LAN media types allows the CSNA feature to take advantage of current source-route bridging (SRB), remote source-route bridging (RSRB), data-link switching plus (DLSw+), Source-Route Translational Bridging (SR/TLB), internal SDLC-LLC2 translational bridging (SDLLC), Qualified Logical Link Control (QLLC) services, and APPN functionality such as SNA Switching Services (SNASw).

Cisco Multipath Channel Environments

CMPC is Cisco's implementation of IBM's MultiPath Channel (MPC) feature on Cisco 7500, Cisco 7200, and Cisco 7000 with RSP7000 series routers. CMPC allows VTAM to establish Advanced-Peer-to-Peer Networking (APPN) connections using both High Performance Routing (HPR) and Intermediate Session Routing (ISR) through channel-attached router platforms.

Routers configured for CMPC can be deployed in Parallel MVS Systems Complex (sysplex) configurations.

CMPC can be used to establish an APPN connection between VTAM and the following types of APPN nodes:

•VTAM on another host that is channel-attached to the same CMCC adapter

•VTAM on another host that is channel-attached to a different CMCC adapter in the same router

•TN3270 server using Dependent LU Requester (DLUR) in the same CMCC adapter

•SNASw in the router with the CMCC adapter

•Other APPN nodes external to the CMCC adapter and router such as Communications Server/2, AS/400, other LAN- or WAN-attached VTAM hosts, or remote routers

One read subchannel and one write subchannel are supported for each MPC transmission group (TG). The read subchannel and write subchannel may be split over two physical channel connections on the same CMCC adapter.

CMPC insulates VTAM from the actual network topology. The MPC protocols are terminated on the CMCC adapter and converted to LLC protocols. After they are converted to LLC protocols, other Cisco features can be used to connect VTAM to other APPN nodes in the network. CMPC can be used in conjunction with DLSw+, RSRB, SR/TLB, SRB, SDLLC, QLLC, ATM LAN emulation, and FRAS host to provide connectivity to VTAM.

CMPC supports connections to PU 2.1 nodes: APPN NN, APPN EN, and LEN. Subarea connections are not supported.

The CMPC feature can coexist with the CLAW, TCP/IP Offload, IP host backup, CSNA, CMPC+, and TN3270 server features on the same CMCC adapter.

Preparing to Configure CSNA and CMPC

The following topics in this section provide information that is useful when you are planning to configure CSNA or CMPC support:

•Hardware and Software Requirements

•Mainframe Host Configuration Considerations

Hardware and Software Requirements

This section provides information about the router and mainframe requirements to support CSNA and CMPC. The router requirements are the same to support either CSNA or CMPC. However, the minimum level of VTAM required on the mainframe varies by whether you are configuring CSNA or CMPC.

Router Requirements

Both the CSNA and CMPC features are supported on the following router platforms:

•Cisco 7500 series—Supports CIP adapters

•Cisco 7200 series—Supports the ECPA and PCPA adapters

•Cisco 7000 series with RSP7000—Supports CIP adapters

You must configure the CSNA and CMPC features on the physical interface of a CMCC adapter. For a CIP, the physical interface is either 0 or 1. For the CPA adapters, ECPA and PCPA, the physical interface is port 0.

Mainframe Requirements

CSNA and CMPC establish channel connectivity to a mainframe host using VTAM on the host. For questions about the required maintenance level or for information about Program Temporary Fixes (PTFs), consult your IBM representative.

The following versions of VTAM are required to configure CSNA and CMPC on a CMCC adapter:

CSNA VTAM Requirement

•VTAM V3.4 and later

CMPC VTAM Requirements

•MPC APPN ISR connections—VTAM V4.2 and later

•MPC APPN HPR connections—VTAM V4.3 and later

Mainframe Host Configuration Considerations

Configuring CSNA or CMPC support requires that you perform tasks for configuration of the mainframe and the router sides of the network environment.

Often in the mixed network environment of mainframes and LANs, an MVS systems programmer installs and maintains the mainframe side of the network, while a network engineer manages the routers on the LAN side of the network. In such an environment, the successful configuration of CSNA or CMPC support requires the close coordination between these job functions at a customer site.

This chapter contains information for both the network engineer and the MVS systems programmer to properly configure the network devices for CSNA or CMPC support. The tasks for configuring CSNA or CMPC support are organized by whether they are host-related configuration tasks or router-related configuration tasks. In addition, a topic for correlating the mainframe and router configuration is provided so that you can identify the dependencies between the host and router configuration elements and be sure that they are set up correctly.

Defining the Channel Subsystem for the Router

To establish the path and allocate the range of subchannel addresses that the CMCC adapter can use for the CSNA or CMPC features, you need to specify the channel subsystem definitions in the Input/Output Control Program (IOCP) or Hardware Configuration Definition (HCD).

For more information about the statements that might be defined in an IOCP file for parallel channels and ESCON channels on the CIP or CPA, see the "Defining the Channel Subsystem for the Router" section in the "Configuring Cisco Mainframe Channel Connection Adapters" chapter of this publication.

Disabling the Missing Interrupt Handler

Because the appropriate configuration of the missing interrupt handler (MIH) varies according to the protocols and software releases used, Cisco offers the following guidance:

•For OS/390 releases Version 2 Release 4 and earlier, set the MIH to zero.

•For OS/390 releases later than Version 2 Release 4 and z/OS releases, refer to the following section of the z/OS Communications Server IP Configuration Reference: http://publibfp.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/f1a1b420/1.2.13?SHELF=f1a1bk31&DT=20020604120755#HDRMOLLY

For information about how to disable the MIH for the unit addresses being used for your CMCC adapter configuration, see the section "Disabling the Missing Interrupt Handler" section in the "Configuring Cisco Mainframe Channel Connection Adapters" chapter of this publication.

CSNA Support Configuration Task List

CSNA allows CMCC adapters to communicate directly with a mainframe host through VTAM. In this capacity, a CMCC adapter running CSNA can replace the functions of a Token Ring subsystem on a channel-attached front-end processor (FEP) or IBM 3172 Interconnect Controller.

This section describes the configuration tasks required to install CSNA support on the mainframe and router and includes the following topics:

•CSNA Configuration Guidelines

•CSNA Host Configuration Task List

•CSNA Router Configuration Task List

•Correlating the Router and Mainframe Configuration Elements

•CSNA Verification Configuration Task List

See the "CSNA and CMPC Configuration Examples" section for examples.

CSNA Configuration Guidelines

To configure the CSNA feature, you must configure the host VTAM parameters and the CMCC adapter. Consider the following guidelines as you begin to configure CSNA support:

•The CMCC adapters communicate with remote SNA nodes using internal LANs (called virtual or pseudo-rings). An internal LAN can have multiple internal adapters and MAC addresses.

•The CMCC adapters support only the Token Ring type of internal LAN.

•A CMCC adapter can have multiple internal LANs, up to a maximum of 18.

Note Although a CMCC adapter can technically support up to 32 internal LANs, the limit of up to 18 internal adapters on a CMCC adapter makes 18 internal LANs the practical limit.

•A CMCC adapter can have multiple internal adapters, up to a maximum of 18.

•To define the host subchannel (or path) and device, use the csna command on the router. The csna command is configured on the router's physical channel interface. On a CIP, the physical interface is on ports 0 and 1. On a CPA, the physical interface is always port 0.

•To configure the internal LANs and adapters, use the following ports on a CMCC interface:

–On a CIP, configure port 2 which is the virtual channel interface.

–On a CPA, configure port 0 which is the physical channel interface.

•To define the internal LAN adapter used by CSNA on the router, create an XCA major node in VTAM. The XCA major node controls the activation and deactivation of subchannels and SAPs associated with the CMCC internal adapters that are configured for CSNA. One XCA major node is required for each internal LAN adapter to be used by the CSNA feature in the router.

•CSNA can coexist with CLAW, TCP/IP offload, CMPC, CMPC+, and TN3270 server features on the router. When you configure multiple entities on a CMCC adapter, it is important to be sure that you do not introduce SAP conflicts.

For more information about configuring SAPs, see the "SAP Configuration Guidelines" section in the "Configuring Cisco Mainframe Channel Connections" chapter in this publication.

•CSNA has a limit of 128 SAPs total on the CMCC. So, if you are configuring the TN3270 server using a CSNA connection, the total number of SAPs open on the host plus the number of SAPs defined for PUs on the TN3270 server must be less than or equal to 128.

•If you are configuring CSNA and the TN3270 server on a CMCC, it is good design practice to configure each feature on a separate internal adapter.

•The adapter number that you specify in the adapter command on the router must match the adapter number defined in the CSNA XCA major node.

•The host IOCP and HCD parameters must coordinate with the csna command parameters on the router and the XCA major node definition to specify the subchannel path, device, and control unit address.

•The unique routing information is determined by a combination of the adapter number, control unit address, and SAP.

CSNA Host Configuration Task List

Configuring CSNA on the mainframe host requires that you establish a path for the CSNA connection by defining the channel subsystem to allocate subchannel addresses, according to the type of router channel connection in use. The tasks in this section assume that the channel subsystem has already been defined to support the CMCC adapter connection.

To establish a SAP for the adapter configured for CSNA in the router, you need to define a VTAM XCA major node. To support the PU type 2.0 and 2.1 connections used in CSNA communication, you need to configure the PU definitions in a switched major node.

This section provides an overview of the primary components needed to implement CSNA on the host. Mainframe systems programmers can use this information as an aid to determine the required parameters to configure CSNA.

The following topics describe the required tasks to configure CSNA on the host:

•Defining the XCA Major Node

•Defining the Switched Major Node

Defining the XCA Major Node

To configure the internal LAN adapter that is used for CSNA support on the router and to specify the subchannel and SAP to be used by the host to communicate with the router, you need to define an XCA major node.

To configure the XCA major node for CSNA support in VTAM, you must know the following information:

•A valid subchannel configured in the IOCP or HCD on the host that can be used for CSNA.

In the following sample configuration, the subchannel address 584 is shown for the CUADDR parameter. In this example, 584 must be one of the available addresses in the IODEVICE statement for the corresponding CMCC channel connection.

•The adapter number configured in the router that identifies the internal LAN adapter. You must define a separate XCA major node for each internal LAN adapter that is configured for CSNA in the router.

In the following sample configuration, the adapter number 0 is shown for the ADAPNO parameter. In this example, 0 must be the number of the adapter defined on the internal LAN for CSNA use in the CMCC.

VTAM allows SAPs to be defined in multiples of 4. SAP 4 is the most commonly used number for SNA. If you need to define multiple XCA major nodes for multiple internal LAN adapters that are configured for CSNA, you can use the same SAP number of 4 in the XCA major node definition because the ADAPNO parameter uniquely identifies the path.

The following sample configuration shows a sample XCA major node definition (labeled JC27A04) that configures an internal LAN adapter numbered 0 on the router with control unit address 584, and defines a SAP of 4:

JC27A04 VBUILD TYPE=XCA

***************************************************************************

PJEC27A PORT ADAPNO=0,                                                   X

             CUADDR=584,                                                 X

             MEDIUM=RING,                                                X

             SAPADDR=04,                                                 X

             TIMER=255

***************************************************************************

JEC27A GROUP DIAL=YES,                                                   X

             ANSWER=ON,                                                  X

             CALL=INOUT,                                                 X

             AUTOGEN=(3,F,E),                                            X

             ISTATUS=ACTIVE

Note The primary configuration elements are shown in bold. All parameters followed by a comma in the PORT and GROUP macros require an X in column 72 as a continuation character.

Defining the Switched Major Node

To support Token Ring PU connections to the host through a CMCC adapter in the router, you need to define switched (dial) connections in VTAM in a switched major node. The remote PUs, defined as PU type 2.0 or 2.1 in the VTAM switched major node, represent the remote SNA controllers (such as an IBM 3174). These PUs can include entities such as a PC running 3270 or APPC emulation packages, PUs configured on DSPU, or a TN3270 server.

The following sample configuration shows a sample switched major node definition labeled C0SWN for a CSNA PU:

C0SWN VBUILD TYPE=SWNET

C0PU1 PU     ADDR=01,                                                    X

             PUTYPE=2,                                                   X

             IDBLK=05D,                                                  X

             IDNUM=C0AA1,                                                X

             MODETAB=ALAMODE,                                            X

             DLOGMODE=SX32702S                                           X

             DISCNT=(NO),                                                X

             USSTAB=USSSNA,                                              X

             ISTATUS=ACTIVE,                                             X

             MAXDATA=521,                                                X

             IRETRY=YES,                                                 X

             MAXOUT=7,                                                   X

             PASSLIM=5,                                                  X

             MAXPATH=4

C0LU101LU    LOCADDR=02

C0LU102LU    LOCADDR=03

C0LU103LU    LOCADDR=04

C0LU104LU    LOCADDR=05

Note The primary configuration elements are shown in bold. All parameters followed by a comma in the PU macro require an X in column 72 as a continuation character.

CSNA Router Configuration Task List

The following sections describe how to configure a CMCC interface for CSNA support. This procedure requires the configuration of both the physical and virtual interfaces on a CIP.

•Configuring the CSNA Subchannels

•Configuring the Internal LAN

•Configuring Internal Adapters

•Configuring the Source Bridge

•Enabling the Router Configuration

Configuring the CSNA Subchannels

Configuring the CSNA subchannels establishes the physical path between the CMCC interface and the mainframe channel.

To define an SNA subchannel supported by the CSNA feature, use the following commands beginning in global configuration mode:


	Command	Purpose
Step 1	Router(config)# interface channel slot/port	Selects the interface on which to configure CSNA. The port value differs by the type of CMCC adapter: •CIP—port value corresponds to the physical interface, which is port 0 or 1. •CPA—port value corresponds to port 0.
Step 2	Router(config-if)# csna path device [maxpiu value][time-delay value][length-delay value]	Defines the CSNA subchannel device with the following arguments: •path—Four-digit value that represents the channel path for the device. The path value is always 0100 for parallel channels. •device—Unit address for the device on the subchannel. The available options for this command are: •maxpiu—(Optional) Maximum packet size (in the range 4096 to 65535 bytes) that the CMCC adapter sends to the host in one I/O operation. The default is 20470 bytes. Note Values for a maxpiu less than 819 bytes are not recommended because of potential LONGREC errors produced by VTAM. •time-delay—(Optional) Maximum allowable delay (in the range 0 to 100 ms) before the CMCC adapter sends packets to the host. The default is 10 ms. •length-delay—(Optional) Minimum data length (in the range 0 to 65535 bytes) to accumulate before the CMCC adapter sends packets to the host. The default is 20470 bytes.

Use the no csna command to remove the CSNA subchannel device.

Mainframe Configuration Tip

Configuring the subchannel information in the router requires that you correlate the path and device information from the IOCP or HCD file on the host.

•The path argument is a four-digit hexadecimal value that concatenates the path value (2 digits), EMIF partition number (1 digit), and control unit logical address (1 digit).

•The device argument is a valid number in the UNITADD range of the IOCP CNTLUNIT statement for the CSNA internal LAN adapter.

For detailed information about how to determine the path and device values for the csna command, see the "Correlating Channel Configuration Parameters" section in the "Configuring Cisco Mainframe Channel Connection Adapters" chapter in this publication.

Configuring the Internal LAN

The CSNA feature resides on an internal LAN and adapter in the CMCC on the router. The internal LAN is a virtual Token Ring LAN that is defined within the CIP or CPA on the router. Unlike the CSNA subchannel path that you define on the physical interface of the CMCC, you define the internal LAN on the virtual interface of the CIP. For the CPA, you can only configure the physical interface port.

To configure an internal LAN, use the following commands beginning in global configuration mode:


	Command	Purpose
Step 1	Router(config)# interface channel slot/port	Selects the interface on which to configure the internal LAN. The port value differs by the type of CMCC adapter: •CIP—port value corresponds to the virtual interface, which is port 2. •CPA—port value corresponds to port 0.
Step 2	Router(config-if)# lan tokenring lan-id	Selects a Token Ring internal LAN interface identified by lan-id and enters internal LAN configuration mode. Note Token Ring is the only type of internal LAN supported on channel interfaces.

Configuring Internal Adapters

To configure CSNA on the internal LAN, you also need to configure an internal adapter for CSNA use on the LAN. Naming the internal adapter is optional. However, selecting meaningful names for the internal adapters that you configure can simplify identification of the adapter in show command output and when troubleshooting is required.

You can configure multiple internal adapters (up to 18) on a CMCC. If you want to support internal adapters with duplicate MAC addresses, you must define the adapter on a different internal LAN and use a unique relative adapter number (RAN). Each internal adapter that is configured for CSNA must have a corresponding XCA major node definition on the host.

To select or configure an internal adapter, use the following commands in internal LAN configuration mode:


	Command	Purpose
Step 1	Router(cfg-lan)# adapter adapno mac-address	Selects the internal adapter to configure for CSNA with the following arguments: •adapno—Relative adapter number (RAN). •mac-address—MAC address for the adapter on the internal LAN. The MAC address cannot be a duplicate on the same internal LAN.
Step 2	Router(cfg-adap)# name name	(Optional) Specifies a name for the internal adapter.

Use the no adapter command to remove an internal adapter.

Mainframe Configuration Tip

The value for the adapno argument in the adapter command on the router must match the value specified for the ADAPNO parameter in the corresponding XCA major node definition in VTAM for CSNA. Each internal adapter that is configured for CSNA must have its own XCA major node definition.

Configuring an Internal Adapter's Link Characteristics

To configure the LLC link characteristics of an internal adapter, use the following commands in internal adapter configuration mode, as needed:


Command	Purpose
Router(cfg-adap)# llc2 n1 bytes	(Optional) Specifies the maximum size (up to 4105 bytes) of an I-frame. The default is 4105 bytes.
Router(cfg-adap)# llc2 n2 retry-count	(Optional) Specifies the maximum retry count (up to 255). The default is 8.
Router(cfg-adap)# llc2 nw window-size-increase	(Optional) Increases the window size for consecutive good I-frames received (0 is disabled). The default is 0.
Router(cfg-adap)# llc2 ack-delay-time milliseconds	(Optional) Specifies the maximum time (up to 60000 ms) for incoming I-frames to stay unacknowledged. The default is 100 ms.
Router(cfg-adap)# llc2 ack-max frame-count	(Optional) Specifies the maximum number of I-frames received (up to 127) before an acknowledgment must be sent. The default is 3.
Router(cfg-adap)# llc2 idle-time milliseconds	(Optional) Specifies the frequency of polls (up to 60000 ms) during periods of idle traffic. The default is 60000 ms.
Router(cfg-adap)# llc2 local-window frame-count	(Optional) Specifies the maximum number of I-frames to send (up to 127) before waiting for an acknowledgment. The default is 7.
Router(cfg-adap)# llc2 recv-window frame-count	(Optional) Controls the number of frames in the receive window. The default is 7.
Router(cfg-adap)# llc2 t1-time milliseconds	(Optional) Specifies the amount of time to wait (up to 60000 ms) for an acknowledgment to send I-frames. The default is 1000 ms.
Router(cfg-adap)# llc2 tbusy-time milliseconds	(Optional) Specifies the amount of time to wait (up to 60000 ms) while the other LLC2 station is in a busy state before attempting to poll the remote station. The default is 9600 ms.
Router(cfg-adap)# llc2 tpf-time milliseconds	(Optional) Specifies the amount of time to wait (up to 60000 ms) for a final response to a poll frame before resending the original poll frame. The default is 1000 ms.
Router(cfg-adap)# llc2 trej-time milliseconds	(Optional) Specifies the amount of time to wait (up to 60000 ms) for resending a rejected frame before sending the reject command. The default is 3200 ms.

Configuring the Source Bridge

Source-route bridging (SRB) is required to get packets from the LANs that are external to the CMCC adapter, to the internal LAN on the CIP or CPA and the CSNA feature. The source-bridge command identifies the interfaces in the same ring group. Frames are sent only to interfaces in the same ring group.

When you configure the source bridge, you can assign the following types of priorities:

•LOCADDR priority—Allows you to maps LUs to queueing priorities for the internal LAN by specifying a defined LOCADDR priority using the locaddr-priority command. The LOCADDR priorities are defined using the locaddr-priority-list command in global configuration mode.

•SAP priority—Allows you to assign priorities for the internal LAN according to the service access point and MAC address in an LLC2 session by specifying a defined SAP priority using the sap-priority command. The SAP priorities are defined using the sap-priority-list command in global configuration mode.

To configure the bridging characteristics for the internal LAN, use the following commands in internal LAN configuration mode:


	Command	Purpose
Step 1	Router(cfg-lan)# source-bridge source-ring-number bridge-number target-ring-number	Configures source-route bridging for the selected internal LAN interface with the following arguments: •source-ring-number—Number for the Token Ring on the internal LAN for the CIP or CPA. •bridge-number—Bridge number connecting the source and target Token Rings. •target-ring-number—Number of the destination ring number on the router. The target ring can also be a ring group.
Step 2	Router(cfg-lan)# locaddr-priority list-number	(Optional) Assigns a LOCADDR priority for the internal LAN, where list-number is a value defined from the locaddr-priority-list command.
Step 3	Router(cfg-lan)# sap-priority list-number	(Optional) Assigns a SAP priority for the internal LAN, where list-number is a value defined from the sap-priority-list command.

Use the no source-bridge command to disable source-route bridging.

Enabling the Router Configuration

After you complete the tasks to configure CSNA on the router, be sure that you enable the configuration using the no shut command on all of the applicable interfaces. For the CIP, this means that you need to run the no shut command on the selected physical interface, and again for the virtual interface.

For the CPA, you only need to run the no shut command on the physical interface.

To enable the router configuration for CSNA, use the following commands beginning in global configuration mode:


	Command	Purpose
Step 1	Router(config)# interface channel slot/port	Selects the interface. The port value differs by the type of CMCC adapter: •CIP—port value corresponds to 0 or 1 for the physical interface, and 2 for the virtual interface. •CPA—port value corresponds to port 0.
Step 2	Router(config-if)# no shut	Restarts the selected interface.

Correlating the Router and Mainframe Configuration Elements

Table 1 shows a summary of the configuration elements on the router and host that must be correlated for proper operation of CSNA. The column labeled "Configuration Element" identifies the type of entity to be configured. The columns labeled "Router Configuration" and "Mainframe Configuration" identify the related parameters on the router and the mainframe whose values must be compatible or match.

Table 1 Relationship of Router and Mainframe Configuration Elements for CSNA
Configuration Element	Router Configuration	Mainframe Configuration
Subchannels	path and device arguments of the csna command	RESOURCE PARTITION, CHPID, and CNTLUNIT statements of the IOCP definition defining the following parameters for the CSNA channel path: •LPAR number (if defined) in the RESOURCE PARTITION and CHPID statements—Specify in the third digit of the path argument in the router csna command. •CUADD value (if defined) in the CNTLUNIT statement—Specify in the fourth digit of the path argument in the router csna command. •Available device address in the UNITADD parameter of the CNTLUNIT statement—Specify in the device argument of the router csna command.
Internal adapter number	adapno argument of the adapter command	ADAPNO parameter in the XCA major node definition for the corresponding CSNA internal adapter

CSNA Verification Configuration Task List

Configuring CSNA includes tasks for both the mainframe and the router. This section describes the steps to verify that you have successfully configured CSNA on a CIP. It provides procedures to verify connectivity from the router perspective and from the host perspective, and includes troubleshooting tips as a guide when the configuration verification fails.

This section includes the following topics:

•Initial Host and Router Configuration

•Verifying CSNA Channel Connectivity

•Verifying Communication with VTAM

Initial Host and Router Configuration

Consider that you begin the verification procedures with the following sample XCA major node definition, switched major node definition, and initial router configuration:

XCA Major Node Definition

JC27A04  VBUILD TYPE=XCA

PJEC27A  PORT ADAPNO=0,                                                 X

              CUADDR=27A,                                               X

              SAPADDR=04,                                               X

              MEDIUM=RING,                                              X

              TIMER=244

JEC27A  GROUP ANSWER=ON,                                                X

              AUTOGEN=(3,F,3),                                          X

              CALL=INOUT,                                               X

              DIAL=YES,                                                 X

              ISTATUS=ACTIVE

Switched Major Node Definition

C0SWN VBUILD TYPE=SWNET

C0PU1 PU     ADDR=01,                                                    X

             PUTYPE=2,                                                   X

             IDBLK=05D,                                                  X

             IDNUM=C0AA1,                                                X

             MODETAB=ALAMODE,                                            X

             DLOGMODE=SX32702S                                           X

             DISCNT=(NO),                                                X

             USSTAB=USSSNA,                                              X

             ISTATUS=ACTIVE,                                             X

             MAXDATA=521,                                                X

             IRETRY=YES,                                                 X

             MAXOUT=7,                                                   X

             PASSLIM=5,                                                  X

             MAXPATH=4

C0LU101LU    LOCADDR=02

C0LU102LU    LOCADDR=03

C0LU103LU    LOCADDR=04

C0LU104LU    LOCADDR=05

Note The verification procedures assume that the XCA major node and switched major node are defined, but not yet activated.

Router Configuration for Internal LAN on a CIP

interface channel 2/1

 no ip address

 no ip directed-broadcast

 no keepalive

interface channel 2/2

 no ip redirects

 no ip directed-broadcast

 no keepalive

 lan Token Ring 0

  source-bridge 100 1 400

  adapter 0 4000.8001.0100

Note The initial router configuration in the "Router Configuration for Internal LAN on a CIP" section shows the internal LAN, source-bridge, and internal adapter configuration in preparation for configuration of CSNA.

Verifying CSNA Channel Connectivity

If you have defined the channel paths for the router at the mainframe host in the IOCP or HCD, you can begin to configure the router for CSNA support and verify connectivity at the channel level first. Isolating this level of verification is useful when the VTAM configuration is not completed, but you want to establish that the router can successfully communicate with the host.

Verifying channel connectivity confirms the following aspects of the router configuration:

•Microcode is loaded on the CMCC

•CMCC adapter is functional

•CMCC can communicate with the host over the channel path

Verifying CSNA Channel Connectivity from the Router

The steps in this section show how to verify the CSNA channel configuration beginning with running the csna command on the router's physical interface. The following assumptions are made for the procedure described in this section:

•The router's virtual interface is already configured with the required internal LAN, source-bridge, and internal adapter statements as shown in the initial router configuration for a CIP in the "Router Configuration for Internal LAN on a CIP" section.

•The router has the recommended CMCC hardware and microcode versions to support the CSNA feature. You can use the show version, show controllers cbus, and show controllers channel commands to verify the Cisco IOS software and CMCC microcode versions.

Note Before you begin on the router, run the debug channel events command so that you can verify the messages on the router console.

To verify CSNA channel connectivity, perform the following steps:

Step 1 From the router, configure the csna command on the physical interface according to your site's requirements as shown in the following example:

interface channel 2/1

csna C190 7A

Confirm that you receive a message stating "Device Initialized," similar to the following display:

C190-7A Device Initialized

Step 2 To verify that the channel is up and the line protocol is up, go to EXEC command mode and run the show interfaces channel command as shown in the following example:

show interfaces channel 2/1

Step 3 To verify that the physical channel is up, run the show extended channel statistics command as shown in the following example:

show extended channel 2/1 statistics

Verify that the path field in the output for the CSNA device shows "ESTABLISHED," which means that the physical channel is up.

Step 4 If your show command output matches the values described in Step 2 and Step 3, then the channel connection between the mainframe and the router is established. If you cannot confirm the values, see the "Troubleshooting Tips for Channel Connectivity" section.

Verifying CSNA Channel Connectivity from the Host

After CSNA has been configured on the router, you can also verify channel connectivity from the host by performing the following steps:

Step 1 From the host, verify that the device is online using the following sample command to display the device:

d u,,,27A

Step 2 If the device is offline, then vary the device online according to your site's configuration as shown in the following sample command:

v 27A,online

Note The CHPID for the device should already be active on the host.

Step 3 If the device comes online, then the channel connection between the mainframe and the router is established. If the device does not come online, or you receive the message "No paths physically available," see the "Troubleshooting Tips for Channel Connectivity" section.

Troubleshooting Tips for Channel Connectivity

There are several indicators on the router and the mainframe that indicate that the channel connection is not available.

•From the router, you might see the following things:

–The output from the show interfaces channel command shows that the channel or line protocol is down.

–The output from the show interface channel statistics command shows that the path is not established (the physical channel is not up).

•From the host, you might see the following things:

–The device is not online.

–When you vary the device online, you receive the message "No paths physically available."

Recommended Action

If you determine that the channel connection is not available, review the following tasks to be sure that you have performed them correctly:

•Be sure that you enabled the CSNA router configuration using the no shut command to restart the interface. If you configured both the physical and virtual interface on a CIP, be sure to run the no shut command on both interfaces.

•Be sure that the CSNA device (and path) are online at the host.

•Verify that the path and device arguments that you specified in your csna configuration command correlate properly to the host IOCP or HCD configuration.

If none of these recommended actions allow you to establish the channel connection, check your CMCC LED indicators and the physical channel connection.

Verifying Communication with VTAM

After the VTAM XCA major node is installed, you can verify communication between the router and VTAM using CSNA. If you have installed a switched major node, you can also verify a session from a network device to the host.

This section includes the following verification procedures:

•Verifying Communication with VTAM from the Host

•Verifying Communication with VTAM from the Router

•Troubleshooting Tips for VTAM

Verifying Communication with VTAM from the Host

This procedure describes how to verify from the host that the XCA major node and switched major node are configured and activated.

To verify communication with VTAM from the host, perform the following steps:

Step 1 If you have configured a switched major node, activate the switched major node from the host using the following sample command:

v net,act,id=C0SWN

Verify that you receive the following console messages:

IST097I VARY ACCEPTED

IST093I C0PU1 ACTIVE

IST093I C0SWN ACTIVE

Step 2 From the host, activate the XCA major node using the following sample command:

v net,act,id=JC27A04

Verify that you receive the following console messages:

IST097I VARY ACCEPTED

IST093I JC27A04 ACTIVE

IST093I C0SWN ACTIVE

If you receive a message similar to the following display, see the "Troubleshooting Tips for VTAM" section:

IST380I ERROR FOR ID=F027A000 - REQUEST: ACTLINK, SENSE: 081C003C

IST380I ERROR FOR ID=F027A001 - REQUEST: ACTLINK, SENSE: 081C003C

IST380I ERROR FOR ID=F027A002 - REQUEST: ACTLINK, SENSE: 081C003C

Step 3 (Optional) Using a network station defined with the proper settings, establish a session with the host. In our example, the station should specify the following parameters:

•MAC address of the adapter on the internal LAN as the destination address—4000.8001.0100

•IDBLK/IDNUM (XID) combination for the destination PU, as defined in the switched major node—05DC0AA1

•Destination SAP, as defined in the XCA major node—4

Display the switched major node using the following sample command, and verify that the PU is active and the corresponding LU shows ACT/S:

d net, id=C0SWN,e

If the PU for the device is not active, see the "Troubleshooting Tips for VTAM" section.

Verifying Communication with VTAM from the Router

This procedure describes how to verify communication with the VTAM XCA major node for CSNA from the router.

To verify communication with VTAM from the router, perform the following steps:

Step 1 Run the show extended channel statistics command as shown in the following example:

show extended channel 2/1 statistics

Verify that the following is displayed in these fields of the output for the CSNA device:

•Path—The CSNA path is "ESTABLISHED," which means that the physical channel is up.

•Con—The connection value is "Y," which means that the subchannel is up and the CSNA connection is established between the router and the mainframe.

Step 2 To verify that the CMCC adapter has opened a SAP, run the show extended channel connection-map llc2 command as shown in the following example:

show extended channel 2/2 connection-map llc2

Step 3 To verify the operational status of the CSNA device, run the show extended channel csna oper command as shown in the following example:

show extended channel 2/1 csna oper

For information about other commands that are useful when diagnosing or monitoring your CSNA connection, see the "Monitoring and Maintaining CSNA and CMPC" section.

Troubleshooting Tips for VTAM

This section describes recommended actions for the following problems that might occur during verification of communication with VTAM.

•From the router, you might see the following output:

–The show interface channel statistics command shows the field Con=N (the subchannel is not allocated). This output is normal if the XCA major node is not active.

•From the host, you might see the following output:

–The IST380I message with sense code 081C003C is displayed when you activate the XCA major node.

–The PU is not active when you display the switched major node after attempting to establish a session.

Recommended Actions

If you encounter problems during verification of communication with VTAM, perform the following tasks to recover:

•If the show interface channel statistics command shows that the path is established (the physical channel is up), but the subchannel is not allocated (Con=N), verify that the XCA major node is activated.

•If you receive the sense code 081C003C when activating the XCA major node at the host, review the following tasks to be sure that you have performed them correctly:

–If you have not already verified channel connectivity, follow the procedure described in the "Verifying CSNA Channel Connectivity" section.

–If the channel connectivity is established, verify the configuration values for the adapter number, control unit address, and SAP.

Be sure that the adapter number that you specified in the XCA major node matches the adapter number on the internal LAN in the router. Verify that the control unit address corresponds to the CSNA device configured on the router and in the IOCP or HCD, and that the SAP is a valid multiple of 4. Be sure that you do not have any SAP conflicts within the router configuration.

•If the PU is not active after attempting to establish a session, verify the values for the following configuration elements in the network device:

–XID value for the destination device matches the IDBLK/IDNUM value in the switched major node.

–Destination MAC address matches the MAC address of the internal adapter in the CMCC.

–Destination SAP address matches the SAP value in the XCA major node. Remember that the SAP address in the XCA major node is in decimal format.

CMPC Support Configuration Task List

CMPC implements the full-duplex IBM channel protocol for SNA, APPN, and HPR traffic. CMPC allows VTAM to establish APPN connections using HPR or ISR through a channel-attached router using a CMCC adapter. CMPC also supports TN3270 using DLUR.

To configure the CMPC feature, you must configure the host VTAM parameters and the CMCC adapter. Consider the following guidelines as you prepare to configure CMPC support: