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KUNBUS GmbH
KUNBUS Ethernet Test Access Point TAP-2100
4 Troubleshooting
No Link on the
Snifferports X1 or X2.
Between the ports ‘Port 1’ and ‘Port 2’ the TX and RX
pins are switched (crossover). There it is necessary to
use a crossover cable on one side of the sniffer if the
devices are not Auto-MDI-X capable.
Not all packets are
displayed in Wireshark.
If the TAP plug-in is not activated, a test sum error may
be displayed. This is due to the additional data TAP
2100 attaches to the packet and it can be ignored.
Wireshark does not
display big packets.
The TAP adds 20 Bytes additional information to the
packets. If a packet is already more than 1480 bytes
long the packet on the output port X0 will exceed the
maximal allowed length of the Ethernet standard and
the packet will be discarded by the network adapter.
To solve this a network adapter that support ‘Jumbo
Packets’ must be used and ‘Jumbo Packets’ must be
enabled in the driver settings.
Packets are displayed as
faulty.
If the TAP plug-in is not activated, a test sum error may
be displayed. This is due to the additional data TAP
2100 attaches to the packet and it can be ignored.
Wireshark displays
additional packets.
It may happen that the PC that runs Wireshark
transmits Broadcast on the interface being used. This is
prevented by disabling all elements (client for Microsoft
networks, internet protocol (TCP/IP), etc.) in the LAN
adapter properties under Windows.
