5 PSF/AIX IPDS Printing Using TCP/IP
This chapter provides details on:
Adding a TCP/IP attached printer
Set up of the KEEPALIVE TCP/IP feature
The basic TCP/IP installation of the PrintServer (IPDS) must be completed before
direct AFP / IPDS from PSF/AIX will be possible.

5.1 Adding TCP/IP attached printer

The port number is defined in the PSF/AIX SMIT Add a TCP/IP-Attached Printer
panel.
1. Enter Printer name
PSF/AIX uses the printer name you specify. Enter a name of up to 8
characters.
2. Enter Internet address
The address in the TCP/IP network where the PrintServer is installed.
Enter a 32-bit dotted decimal notation (e.g. 192.0.2.1).
3. Enter Port number (5001)
If the output device is attached to PARALLEL 1 of the print server, then
select TCP/IP port number 5001. The value chosen must match the value
defined for the session in the PrintServer (IPDS). 5001 is the default port
number of the first IPDS port no. in the PrintServer (IPDS).

5.2 KEEPALIVE support for AIX

The TCP/IP components in AIX offer network attachment for printers. However,
these TCP/IP components do not always detect connection failures if a point-to-
point session between the AIX machine and the device has failed (e.g. in
connection with a printer being abruptly powered off). This may result in serious
problems for IPDS printers in sessions with PSF/AIX
Now, support for the TCP KEEPALIVE facility has been added to the TCP/IP
components of AIX to detect all communication failures. PSF/AIX directs TCP to
send a KEEPALIVE transmission on a TCP connection remaining inactive for an
extended period. If the KEEPALIVE transmission is not acknowledged, the TCP
assumes that the connection partner has been lost and subsequently reports a
failure to PSF/AIX
The frequency of these transmissions depends upon the configuration of AIX
TCP/IP environment. The default for AIX is two hours or more. This, however, can
be adjusted. These values apply to all TCP applications that request KEEPALIVE
transmissions.
In the following, you are provided with instructions for using the KEEPALIVE
support facility added to the TCP/IP components for AIX
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