Modify the TCP/IP Profile in z/OS
The TCP/IP profile contains system configuration statements used to initialize the TCP/IP address space.
The following statements in the TCP/IP profile; however, this example is not a complete profile.
• If you change any of the values in the TCP/IP profile, restart TCP/IP to pick up the changes.
Sample Parameters in the TCP/IP Profile.
This example is not a complete TCP/IP profile.
The statements require special considerations when you are printing from PSF on TCP/IP-attached
printers:
•
TCPIPCONFIG
The TCPIPCONFIG statement defines the interval between keep-alive transmissions. PSF relies on
TCP to detect when a connection with a TCP/IP-attached printer or an i-data 7913 IPDS™ Printer
LAN Attachment is no longer usable. When no data has been exchanged between PSF and its
connection partner, TCP sends keep-alive probes to the connection partner periodically.
These periodic probes, called keep-alive transmissions, enable TCP to discover when a connection
is no longer usable even if the connection partner is abruptly powered off or is no longer
accessible through the network.
The frequency of keep-alive transmissions is controlled by the INTERVAL parameter on the
TCPIPCONFIG statement. The frequency applies to all TCP applications that direct TCP to send
keep-alive transmissions. The default frequency is after about two hours of inactivity.
For printing on TCP/IP-attached printers, we recommend that you specify a shorter interval than the
default, such as 1 minute, for the interval between keep-alive transmissions.
Also, if any target host requires that the keep-alive packet contain data, specify SENDGARBAGE
TRUE. For example:
TCPIPCONFIG INTERVAL 1 SENDGARBAGE FALSE GATEWAY
• GATEWAY
The GATEWAY statement defines a static route to the printer.
Verify the Printer Connection
To verify that z/OS can establish a connection with the TCP/IP-attached printer, ping the printer from
the z/OS system.
From a TSO session, enter the following command:
TSO PING ip_address
4. Configuring z/OS to Print IPDS Files
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