SNA Server/6000 Setup

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AIXLink/X.25 1.1 for AIX: Guide and Reference

SNA Server/6000 Setup

The following is a step-by-step description of how to customize SNA Server to use emulation within an X.25 network.

The steps below are described in the subsequent sections.

Customizing SNA Server/6000 to Use Emulation

Install the SNA Server/6000 Licensed Program Product.
Install the Qualified Logical Link Control (QLLC) device driver.
Get host definitions.
Physical unit (PU T2.1) setup:
- Define the X.25 Link Station.
- Define the X.25 SNA DLC.
Logical unit (LU 2) setup:
- Define the LU profiles for communications.
Verify SNA profiles.
Start SNA.
- Start SNA Server/6000 server.
- Start link station.
- List current status of .

Installation of the Program

The licensed program product, program number 5765-247, consists of the following parts:

snamEn_US.msg	Contains the messages and helps in the specified language for the run-time environment. If you install multiple languages for a product, be sure that you install the preferred (or primary) language first.
sna.sna.obj	Contains the base program.
sna.lu0.obj	Contains the LU0 facility.

The licensed program may also contain update files.

Installation of the Qualified Logical Link Control

The Qualified Logical Link Control (QLLC) is the AIX device driver that is used by to communicate through the supported X.25 adapters. QLLC has a special file under the /dev directory named, dlcqllc.

To show the predefined device information for QLLC:

# lsdev -P -H -c dlc -t x25_qllc

class type       subclass   description

dlc   x25_qllc     dlc      X.25 QLLC Data Link Control

Each of the above corresponds to one of the physical interfaces supported by SNA communications in AIX.

You can use one of the following methods to install the X.25 QLLC Data Link Control:

To use the SMIT fast path, enter:
```
smit cmddlc_qllc_mk
```
To use SMIT , enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Devices.

Select Communication.

Select the appropriate adapter, either:
- Portmaster Adapter/A
- X.25 CoProcessor/2 or Multiport/2 Adapter
Select Services.
Select Data Link Controls.

Select Add a QLLC Data Link Control.
To install the X.25 QLLC Data Link Control from the command line, enter:
```
mkdev -c dlc -s dlc -t x25_qllc
```

Getting Host Definitions

To start configuring , request some information from the () administrator for the SNA node you want to connect to. The following table is the minimum information required in this example:

SNA Host Definitions
VTAM Parameter	Value	Profile
Network User Address	3106001984	Link station profile
IDBLK	071	3270 LU profiles
IDNUM	06000	3270 LU profiles
SSCP ID	20	3270 LU profiles
LOCADDR	2, 3	3270 LU profiles

Network User Address:	The X.25 address, 3106001984, uniquely identifies the X.25 line to which the System/370 host is attached. This parameter is used in the "Link station profile" definition.
IDBLK	The three hexadecimal digits of this parameter provide an identifier, or block number, that is unique to each product on the network. For the RS/6000, this number is 071.
IDNUM	The five hexadecimal digits of this ID number distinguish a specific piece of equipment from all others of a similar kind on the network. The number usually is given by the administrator. In our case, an ID number of `06000` was assigned to our RS/6000.
SSCPID	The ID of the controlling System Services Control Point (SSCP) in the SNA network(decimal value).
LOCCADR	Local addresses of the displays and printers in the cluster. One decimal value is used for each display or printer connected.

SNA Profiles for an X.25 LU2

The Logical Unit Type2 (LU2) Profiles figure shows the profiles needed to configure a logical unit type 2 (LU2).

Setup of the SNA Physical Unit

Setting up the SNA physical unit consists of the following steps:

Defining the X.25 Link Station
Defining the X.25 SNA DLC

Defining the Link Station Profile

Use one of the following methods to enter the link station information.

Using the SMIT fast path, enter:
```
smit _snaX25attcmk
```
Using SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services

Select SNA Server/6000

Select Configure SNA Profiles

Select either: Quick Configuration or Advanced Configuration

If you selected Quick Configuration:

Select Quick Configuration for Link Stations

Choose DLC type of x.25_pvc or x.25_svc

Enter:    Link station name   []

   Calling link station? (call or listen)   yes/no

   Remote X.25 station address   []

If you selected Advanced Configuration:

Select Links

Select X.25

Select X.25 Link Station

Select Add a Profile

Enter:         Profile name

                     SNA DLC Profile name

Both of these methods display the Add X.25 Link Station Profile screen. This screen contains fields in which you type or select the desired values. The following example shows the entry fields with sample field values:

Add X.25 Link Station Profile
Type or select values in entry fields.
Press Enter after making all desired changes.
[TOP}     [Entry Fields]
* Profile Name      []        +
  Use Control Point's XID node ID?                     yes
      If no, XID node ID                               [*]               +
* SNA DLC Profile name                                 []]               +
  Stop link station on inactivity?                     no]               +
      If yes, Inactivity time-out (0-10 minutes) [0]   #
  LU address registration?                             no]               +
      If yes, LU Address Registration Profile name     []]               +
  Trace link?                                          no]               +
      If yes, Trace size                               long]             +
    X.25 level                                         1984]             +
  Station type                                         secondary]        +
  Adjacent Node Identification Parameters
      Verify adjacent node?                            no]               +
      Network ID of adjacent node                      []]         
      CP name of adjacent node                         []]          
      XID node ID of adjacent node (LEN node only)     [*]]  
      Node type of adjacent node                       learn]            +
  Link Activation Parameters
      Solicit SSCP sessions?                           yes]              +
      Initiate call when link station is activated?    yes]              +
      Virtual circuit type                             switched]         +
         If permanent,
            logical channel number of PVC (1-4095)     [1]]              #
         If switched,
            Listen name                                [IBMQLLC]]   
            Remote station X.25 address                []]               +
            X.25 Optional Facilities Profile name      []]               +
      Activate link station at SNA startup?            no]               +
      Activate on demand?                              no]               +
      CP-CP sessions supported?                        yes]              +
         If yes, 
            Adjacent network node preferred server?    no]               +
      Partner required to support CP-CP sessions?      no]               +
      Initial TG number (0-20)                         [0]]              #
   Restart Parameters
      Restart on activation?                           no]               +
      Restart on normal deactivation                   no]               +
      Restart on abnormal deactivation?                no]               +
      Transmission Group COS Characteristics
         Effective capacity                            [9600]]           #    
         Cost per connect time                         [128]]            #    
          Cost per byte                                [128]]            #    
         Security                                      public_switched_networ> +    
 
       Propagation delay                               packet_switched_networ> +    
         User-defined 1                                [128]]            #    
         User-defined 2                                [128]]            #    
         User-defined 3                                [128]]            #    
 
      Comments                                         []

Defining the SNA X.25 DLC Profile

Use one of the following methods to enter the SNA DLC profile information.

Using the SMIT fast path, enter:
```
smit _snaX25linkmk
```
Using SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services

Select SNA Server/6000

Select Configure SNA Profiles

Select Advanced Configuration

Select Links

Select X.25

Select X.25 SNA DLC

Select Add a Profile

Enter: Profile name

Both of these methods display the Add X.25 SNA DLC Profile screen. This screen contains fields in which you type or select the desired values. The following example shows the entry fields with sample field values:

Add X.25 SNA DLC Profile
Type or select values in entry fields.
Press Enter after making all desired changes.
                                                            [Entry Fields]
* Profile Name                                              []           +
   Data link device name                                    [x25s0]      +
   Force disconnect time-out (1-600 seconds)                [120]        #
   User-defined maximum I-field size?                       no           +
      If yes, Maximum I-Field size (265-30729)              [1417]       #
   Maximum number of active link stations (1-255)           [100]        #
      Number reserved for inbound activation                [0]          #
      Number reserved for outbound activation               [0]          #
   Local X.25 network address                               []           #
   Receive window count (1-127)                             [2]          #
   Transmit window count (1-120)                            [2]          #
   Secondary and Negotiable Stations
      Secondary inactivity time-out (1-255 seconds)         [30]         #
   Primary and Negotiable Stations
      Primary repoll frequency (1-255 seconds)              [30]         #
      Primary repoll count (1-255)                          [10]         #
  
 Link Recovery Parameters
      Retry interval (1-10000 seconds)                      [60]         #
      Retry limit  (0-500 attempts)                         [20]         #
Comments                                                    []

Defining the SNA QLLC Logical Link Profile

This profile describes the characteristics of the link protocol used on the network. Several timers and an I_FIELD can be defined here.

Use one of the following methods to enter the SNA QLLC profile information.

Using the SMIT fast path, enter:
```
smit cmddlc_qllc
```
Using SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Devices

Select the appropriate device, either:
- Portmaster Adapter/A
- X.25 CoProcessor/2 or Multiport/2 Adapter
Select Services
Select Data Link Controls

Select Add a QLLC Data Link Control

Choose dlc x25_qllc dlc X.25 QLLC Data Link Control as the name of the device to add.

Defining the LU Profiles for Communication

You can allow the system to define and generate the LU profiles required for communications, or you can define the profiles yourself. If you must specify host LU names to be used by the system, you can define the LU profiles yourself, or you can let the system define them initially, and then you can change the individual profiles.

There are two methods for defining the LU profiles for communication: a generic way allowing profiles to be generated "automatically," and a "manual" process. In certain situations you may have to specify host LU names to be used by the system. If this is the case, you can either use the manual process to generate LU profiles, or use the automatic process initially, and then change the individual profiles.

System-Defined LU Profiles

When you are configuring SNA for a emulator, you can use SMIT to create the following profiles in one operation:

The SNA control point profile (first time only).
The LU2 session profile.

Use one of the following methods to enter the link station information.

Using the SMIT fast path, enter:
```
smit _snaqc3
```
Using SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services

Select SNA Server/6000

Select Configure SNA Profiles

Select Quick Configuration

Select Quick Configuration for a 3270 Communications Session

Enter: Quick Configuration name (maximum 12 characters) []

Locate the text: Do you wish to configure to an existing network link station ? and do either of the following:
- Choose yes to use an Existing Link Station screen to specify a Link Station Profile name. Next, enter the Link Station Profile name or select one from the list []. This brings up the Quick Configuration for a Communications Session screen. Then, provide LU addresses (values of 1-255) or address ranges for the appropriate LU types (LU1, LU2, or LU3).
- Choose no to use a New Link Station dialog to select a link station type identifier. Then choose a default network link station type from the following list:
  x.25_listen
  
  x.25_call_PVC_pri
  
  x.25_call_PVC_sec
  
  x.25_call_SVC

In both methods, SMIT uses the Quick Configuration name and the address (or address range) to build the session profile.

Quick Configuration for a 3270 Communications Session: Information
Type or select values in entry fields.
Press Enter after making all desired changes.
 
                                              [Entry Fields]
* Quick configuration name                    s3270
   Link Station                               LCLLNKx
   Link station type                          S.25
   Remote X.25 station address                [3000]            #
   System services control point 
      (SSCP) ID (*, 0-65535)                  [*]
   XID node ID                                [*]
   Provide LU addresses (values of 1-255) or address ranges for 
   any of the following LU types:
      LU1                           []
      LU2                           []
      LU3                           []

The entry fields for the Communications Session screen are defined as follows:

Link Station	Shows either the name of the Link Station Profile specified earlier (if you are configuring to an existing link station) or the link station type you specified (if you are creating a new link station).
Link Station Type	Appears on this dialog only when you are configuring to an existing link station, and shows the type of that link station.
Remote X.25 Station Address	Specifies the X.25 address of the remote link station.
System Services Control Point	Specifies the node ID of the system services control point (SSCP) in the SNA network that controls this dependent LU. To allow any host to initiate sessions with the local LU being defined, leave the default value in this field. The SSCP ID is defined in the SSCPID= field of the Start statement. Contact the network administrator for the host system to find out the value to enter in this field. The definitions specify this value in decimal, but requires a hexadecimal value. The format of this field value is: 05000000xxxx where xxxx represents the hexadecimal value of the SSCP ID. A single * (asterisk) in the SSCP ID field can be used to allow any host to initiate a session with this LU as long as the local LU address matches that of the received session initiation request from the host.
XID node ID	Provides an identifier for the physical unit associated with this link station, to be exchanged with an adjacent node during link activation. The XID exchange helps ensure that the correct physical units are being connected.

If you are connecting to a host over a switched connection, enter a value in this field to support dependent LU sessions with the host. To support multiple host connections, you must create additional link station profiles using Advanced Configuration.

If this node does not use any switched connections, use the default value for this field.

This field has two parts:

Block Number The first three hexadecimal digits provide an identifier, or block number, that is unique to each product on the network. For example, the value of 071 identifies the local node as a RS/6000 workstation.
If you are connecting to a host, the block number you specify must match the IDBLK= parameter in the PU definition statement. Contact the network administrator at the host system to find out the value for this field.
ID Number The last five hexadecimal digits distinguish a specific piece of equipment from all other similar pieces of equipment on the network. If you are creating your own network, you can choose any unique identifier, such as a sequence number, for each member of the network. If you are configuring a link to a network that uses other equipment, see the equipment documentation for the recommended method for choosing an ID number.
If you are connecting to a host, the ID number is the IDNUM= parameter in the PU definition statement. This number is a five-digit hexadecimal number assigned by the host system programmer. It is frequently set to the device serial number. Contact the network administrator at the host system to find out the value for this field.

LU Addresses

Specifies the number or range for the particular type display or printer connected to the emulated control unit. This value corresponds to the LOCADDR parameter.

After the above information is entered, the configuration process is complete, session profiles are constructed by appending the local addresses to the quick configuration name.

User-defined LU Profiles

You can use SMIT to create the three SNA configuration profiles. Define these profiles in the following order: first, the control point profile; then the logical unit profiles; and finally, the logical connection profiles.

You can use one of the following methods to create the control point profile:

Using the SMIT fast path, enter:
```
smit _snacpch
```
Using SMIT, enter:
```
smit 
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services

Select SNA Server/6000

Select Configure SNA Profiles

Select Advanced Configuration

Select Control Point

Select Change/Show Control Point Profile

Both of these methods display the Change/Show Control Point Profile screen. The following example shows the entry fields on this screen with sample values.

Change/Show Control Point Profile
Type or select values in entry fields.
Press Enter after making all desired changes.
                                                [Entry Fields]
* Profile name                                  node_cp
   XID node ID                                  [*]
   Network name                                 [MERLIN]
   Control Point (CP) name                      [SNA18]
   Control Point alias                          [SNA18]
   Control Point type                           appn_end_node   +
   Maximum number of cached routing trees       [500]           #
   Maximum number of nodes in the TRS database  [500]           #
   Route addition resistance                    [128]           #
   Comments                                     []

Enter or select the values for the fields and then press enter to create the control point profile. After you create the control point profile, define the LU2 Session profile.

You can use one of the following methods to create the control point profile:

Using the SMIT fast path, enter:
```
smit _snasess2mk
```
Using SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services

Select SNA Server/6000

Select Configure SNA Profiles

Select Advanced Configuration

Select Sessions

Select LU2

Select Add LU2 Session Profile

Both of these methods display the Add LU2 Session Profile screen. The following example shows the entry fields on this screen with sample values.

Add LU2 Session Profile
Type or select values in entry fields.
Press Enter after making all desired changes.
                                         [Entry Fields]
* Profile name                           []
   Local LU name                         []
* Local LU address (1-255)               []              #
   System services control point
      (SSCP) ID (*, 0-65535)             [*]
   Link Station Profile name             []
   Network name                          []
   Remote LU name                        []
   Maximum number of rows                [24]            #
   Maximum number of columns             [80]            #
   Comments                              []

You must repeat this process for each LU2 session.

Verifying SNA Profiles

Use one of the following methods to verify the SNA profiles.

To verify the SNA profiles from the command line, enter:
```
verifysna -U
```
The verifysna command checks for correct cross-reference of profiles. It verifies, for example, that your link station profile points to an existing SNA DLC profile.
To use SMIT, enter:
```
smit
```
and make the following selections from the SMIT menus:
Select Communications Applications and Services.

Select SNA Server/6000.

Select Configure SNA Profiles.

Select Verify SNA Configuration Profiles.

Start Server

Before any application such as HCON can use , the SNA server must be running or active.

To start the SNA server, log in as the root user and enter the following command:

sna -s

Start Link Station

Usually it is not necessary to explicitly start a link station. When an application opens a communications link, the process activates the associated session and link station.

You can explicitly start a link station to test the integrity of the physical unit (PU) profiles.

Starting the link station begins the physical connection with the host, so a call request packet is sent from the X.25 adapter.

To start a link station, log in as the root user and enter the following:

sna -s l -p Link_Station_Profile_Name

List Current Status of

You can obtain status information about by logging in as the root user and entering the following command:

sna -d l

This command displays the status of the SNA link stations and produces output similar to the following:

Link     Adjacent          Node     Device              # of Local    In
Station  CP Name           Type     Name      State     Sessions      Use
-------  --------          ----     ------    -----     ----------    ----
hx25_att  USIBMTH.TH2VTAM   LEN      x25s0     Active    9             Yes

The status of the SNA program and link station must be active, meaning they are operational. If this is not the case, contact your administrator and request the link to be varied on. If you still have a problem, check the SSCP ID and XID, as incorrect values for these parameters are the source of most problems.

To obtain the status of SNA LU6.2 Sessions enter:

sna -d s

This command displays the status of the SNA LU6.2 sessions and produces output similar to the following:

         Local             Partner        Mode      Link
CGID     LU Name           LU Name        Name      Station      State
----     --------          --------       -----     -------      -----
9        USIBMTH.XLUD03                             hx25_att     Available
8        USIBMTH.XLUD02                             hx25_att     Available

To obtain the status of SNA LU1, LU2, and LU3 sessions, enter:

sna -d s123

This command displays the status of the SNA LU1, LU2, and LU3 sessions and produces output similar to the following:

                                                   Local
Local     LU        Session   Session        LU     Host      Link
ID        Type      Type      Profile Name   Addr   SSCP ID   Station     State
-----     ----      -------   ------------   ---- -------     --------   -------
7         2         SSCP-LU   hx25_lu2c07    7      4672      hx25_att    Active
6         2         SSCP-LU   hx25_lu2c06    6      4672      hx25_att    Active
5         2         SSCP-LU   hx25_lu2c05    5      4672      hx25_att    Active
4         2         SSCP-LU   hx25_lu2c04    4      4672      hx25_att    Active
3         2         SSCP-LU   hx25_lu2c03    3      4672      hx25_att    Active
2         2         SSCP-LU   hx25_lu2c02    2      4672      hx25_att    Active
1         2         SSCP-LU   hx25_lu2c01    1      4672      hx25_att    Active

See the AIX SNA/Server Command Reference, Order Number SC31-7100, AIX SNA Server/6000: Configuration Reference, Order Number SC31-7014, and AIX SNA Server/6000: User's Guide, Order Number SC31-7002 for additional information about using SNA and X.25.

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