Installation and Setup ida ReRouter

4.3 Keep Alive Function

The KEEPALIVE feature is a monitor function to check the conneciton between the transaction program (i.e. the ida ReRouter program) and the printer. The monitoring of the conneciton is done at defined intervals.

4.3.1 Support for KeepAlive to OS/2

The TCP/IP components for OS/2 offer network attachment for printers. However, these TCPIP components do not always detect connection failures if a point-to-point session between the OS2 machine and the device has failed (e.g. in connection with a printer being abruptly powered off). This may result in serious problems if the printers comprise IPDS printers in sessions with PSF/2 or PSF/6000.

Now, support for the TCP KEEPALIVE facility has been added to the TCP/IP components for OS/2 to detect all communcation failures. The PSF/6000 or PSF/2 direct 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 the PSF/6000 or PSF/2.

The frequency of these transmissions depends upon the configuration of the TCP/IP in the OS/2 environments. On OS/2, the default values are two hours or more. Both platforms, however, allow the frequency of KEEPALIVE transmissions to 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 OS/2.

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I-Data ReRouter instruction manual Keep Alive Function, Support for KeepAlive to OS/2