Defining local major nodes

A local-attached configuration is defined to VTAM® as using a local major node. For example, for a printer connected to an LU type 1 control unit, the connection between VTAM and the control unit is defined with a PU statement. Each printer attached to the control unit is defined with an LU statement. Figure 20 shows an example.

Figure 20. Example showing three local major nodes. A node can be for either a printer or a control unit.

Figure 21 shows an example of VTAM definitions for local major nodes.

For an LU type 6.2 device
 
CHAN3TST  VBUILD  TYPE=LOCAL
PUYALE8   PU      CUADDR=nnn,MAXBFRU=13
LUYALE8   LU      LOCADDR=1,DLOGMOD=IBM3820C,MODETAB=MODETAB1
 
For an LU type 1 device
 
LOC3812   VBUILD  TYPE=LOCAL
PU13812   PU      CUADDR=nnn,MAXBFRU=2
LU13812   LU      LOCADDR=8,MODETAB=MODETAB1,DLOGMOD=IBM3812C,ISTATUS=ACTIVE
 

VBUILD

Describes the node.

TYPE=LOCAL

Specifies a local major node.

PU

Describes the physical unit. For LU type 1 printers, the PU is the control unit.

CUADDR

Specifies the hexadecimal channel-device name to be used when activating the PU. The value must match the channel-device name specified in the device configuration for the control unit or printer connected to the host.

MAXBFRU

Specifies, as a decimal integer, the number of buffer units (elements of the IOBUF buffer pool) that are used for data by VTAM. The number of buffers depends on the maximum RU size and the size of the IOBUF elements. For information about customizing this value, see your publications for VTAM.

LU

Describes the logical unit (LU). The name specified on the LU statement must also be specified on the LU name parameter in the Printer Inventory (see LU name) or the LUNAME parameter in the PRINTDEV statement of the PSF startup procedure (see LUNAME).

DLOGMOD

Specifies the name of the VTAM logon-mode table entry if one is not otherwise provided. The name must match the LOGMODE operand of the MODEENT statement for the entry. For more information, see Defining the logon-mode table entry.

This parameter is required when Management mode=Dial in is specified in the Printer Inventory (see Management mode) or MGMTMODE=DIALIN is specified in the PRINTDEV statement of the PSF startup procedure (see MGMTMODE).

If Logmode is specified in the Printer Inventory (see Logmode) or LOGMODE is specified in the PRINTDEV statement (see LOGMODE), it overrides the name specified here when either Management mode=Immediate or Management mode=Output available is specified in the Printer Inventory, or MGMTMODE=IMMED or MGMTMODE=OUTAVAIL is specified in the PRINTDEV statement.

ISTATUS={ACTIVE|INACTIVE}

Specifies whether this logical unit is to be activated when the major node is first activated.

LOCADDR

Specifies the LU address at the PU. For 3820 or a 3935 printer, LOCADDR=1. For an LU1 printer, use the address of the printer line coming from the control unit. For example, for a 3174 control unit that is using LU1, this value equals the port number of the printer plus 2.

A LOCADDR of X'00' defines the LU as an independent LU, and all sessions use the same X'00' LU address.

A LOCADDR of X'01' through X'FF' defines the LU as a dependent LU, and each session must have a unique LU address.

LOGAPPL

Specifies the name of the application program and must match the name specified in the Applid parameter in the Printer Inventory (see Applid) or the APPLID parameter in the PRINTDEV statement (see APPLID). This parameter is required only when Management mode=Dial in is specified in the Printer Inventory (see Management mode) or MGMTMODE=DIALIN is specified in the PRINTDEV statement (see MGMTMODE). For more information, see the note in APPL.

Note:

When LOGAPPL is specified, the host application program node must be active before the device LU node is activated. Also, if Management mode=Dial in is specified in the Printer Inventory or MGMTMODE=DIALIN is specified in the PRINTDEV statement, printers cannot be shared.

MODETAB

Specifies the name of the logon-mode table if it is defined locally. If it is not specified, the logon-mode table supplied by IBM® is used.

PACING

Determines how VTAM paces the flow of data from the boundary node, which performs pacing for the physical unit to the secondary logical unit (SLU). Zero means no pacing.

VPACING

Determines how VTAM paces the flow of data from the host system to the boundary node, which performs pacing for the physical unit. Zero means no pacing.