User's Manual

ETHERNET TO TWINAX/COAX PRINT SERVER

KEEPALIVEOPTIONS: PSF relies on TCP to detect when a connection with a

print server is no longer usable. When no data has been exchanged between

PSF/MVS and the print server, TCP periodically sends keep-alive probes to the

print server. These periodic probes, called keep-alive transmissions, enable TCP to

discover when a connection is no longer usable, even if the print server 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 KEEPALIVEOPTIONS 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 an print server, it is recommended that you specify a shorter

interval than the default, such as 10 minutes, for the interval between keep-alive

transmissions. Also, if any target host requires that the keep-alive packet contain

data, include the statement SENDGARBAGETRUE.

GATEWAY: The Packet_size parameter of the GATEWAY statement defines the

maximum transmission unit (MTU) for the MVS host. For network printers, the

MTU size is fixed at 1024 bytes. The value cannot be adjusted.

8.2.4 V

ERIFY THE

RINTER

ONNECTION

ING THE

RINT

ERVER

)

To verify that the IBM MVS system can establish a connection with the print server,

ping the print server from the MVS system.

• From a TSO session, enter the following: TSO Ping ip_address

• In JES2, enter the following command from the System Display and Search

Facility (SDSF) menu 6: ping ip_address

The ip_address specifies the IP address of the NIC. The following shows examples

of a successful ping and an unsuccessful ping.

Successful ping:

EZA04581 Ping V3R1: Pinging host 9.99.12.33

(Use ATTN to interrupt.)

EZA04631 PING: Ping #1 response took 0.084 seconds.

Successes so far = 1.