Step 2—3270—Setting the Number of Virtual Devices
The server system uses virtual devices to direct output to devices on your system.
AS/400 Telnetserver support automatically selects (and creates, if necessary) these
devices for you. Youmay also choose to create your own virtual device under the
QVIRCDnnnn virtual controller. Note that virtual devices that you create under
QVIRCDnnnn will not be auto-selected. This would require a user exit program or
client subnegotiation to select this device.
The option is available for you to allow the Telnetserver support on the AS/400
system to automatically configure virtual controllers and devices. The QAUTOVRT
system value specifies the maximum number of devices that are automatically
configured by the system. Use the Change System Value (CHGSYSVAL)command
to change the value of the QAUTOVRT system value. For example, entering the
following command string changes the number of virtual devices that can be
allocated on a system to 50:
CHGSYSVAL SYSVAL(QAUTOVRT) VALUE(50)
Note: QAUTOVRT has been modified for Version4 Release 2 to support numeric
values of 0 through 32500, and a special value of *NOMAX.
Todetermine and set the maximum number of users you want signed on to the
AS/400 system at any time, do the following:
1. Set the QAUTOVRT value to 32500, the maximum value allowed, or use the
*NOMAX value.
2. Let your users use pass-through, Telnet,the virtual terminal application program
interface and TelnetPrinter pass-through until you decide that the number of
virtual devices created is sufficient for normal system operation.
3. Change the QAUTOVRT value from 32500 to the number of virtual devices you
require for normal system operation.
If you have never allowed automatic configuration of virtual devices on your system,
the QAUTOVRT value is 0.A Telnet connection attempt with a dependence on
automatic creation of the virtual device then fails because the Telnetserver does
not create more than the specified QAUTOVRT devices (zero). If you try to connect,
you receive a message (TCP2504) indicating that the Telnetclient session has
ended and the connection is closed. In addition, the QTGTELNETS job in the
QSYSWRK subsystem on the AS/400 Telnetserver sends a message (CPF8940)
indicating that a virtual device cannot be automatically selected.
If you change the QAUTOVRT value to 10, the next Telnetconnection attempt
causes the Telnetserver to create a virtual device. This virtual device is created
because the number of virtual devices on the controller (0) is less than the number
specified in the QAUTOVRT (10). Even if you change the specified number to 0
again, the next user attempting a Telnetconnection succeeds. When a Telnet
connection attempt fails, the CPF87D7 message is sent to the system operator
message queue on the Telnetserver system. The CPF87D7 message indicates that
the AS/400 server is not able to create a virtual device.
The Telnetserver uses the following conventions for naming virtual controllers and
devices:
vVirtual controllers are named QPACTLnn.
188 OS/400 TCP/IPConfiguration and Reference V4R4