Printronix Network Interface Card, Руководство пользователя

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Printer Logging Through Logpaths
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Periodic Ping
This feature when enabled executes background ping from the print
server to its default gateway. The operation is executed on every
user defined period. This mechanism has no TCP traffic from the
print server to anything on the network to keep route information
alive. Since every member in the VLAN is subject to aging from
bridging cache, a switch or bridge in between may be forgotten in
the table at which port the printer was connected. If one ping is run
from printer server to its default gateway through the switch, the
switch learns again and the route is seen. The problem will not be
seen with TCP since the ACKs keep the bridge relearning in a
switch. Periodically send ICMP Echo Request between a print
server and its gateway that is typically situated in the same VLAN
and connected with the same switch or bridge.
The printer server allows a periodic group of ping packets [1 – 5] to
be issued by a set time [1– 5] minutes, to the gateway value the
NIC has from its routing table. This feature can be enabled or
disabled. The default is disable.
This periodic ping is different from the normal ping process. The
purpose of this ping is not an attempt at dead gateway detection.
There is no ping client created in the print server and the ICMP
Echo Reply packets received from the gateway are deleted without
being processed by the ping client. This reduces the processing
load on the print server. The data size of ICMP Echo Request
Message is set to 16 bytes such that the Ethernet frame is set to
64 bytes to minimize the impact of bandwidth on the network. This
process applies to all the active NIC interfaces.
Periodic Ping