Chapter 9 - Troubleshooting - Multitech RouteFinder RF850 User Manual

Chapter 9 – Troubleshooting
Before you call the Technical Support, check the following:
1. Review the RouteFinder FAQs in the previous section.
2. Verify that the pre-installation requirements are met. Refer to Chapter 2 of this manual.
3. Verify that the Administrations PC requirements are met (correct Default Gateway configuration, using an
HTTPS-compatible Browser, JavaScript and Cascading Style active, and Proxies deactivated in the
browser).
4. If you can't establish a connection and the message "Error: The <software> is not reachable from the
local network" is displayed, try the following:
•
verify IP Addresses in the software are correctly configured
•
verify IP Address of the Client PC is correctly configured
•
verify Default Gateway of the Client PC is correctly configured
•
verify proper Network Cable installation
5. Check for updates to the product documentation on the Multi-Tech Web site at
http://www.multitech.com/DOCUMENTS/.
6. To troubleshoot TCP/IP connections in Windows 2000, use the Ping, Tracert, and Pathping commands. The
Ping command sends an Internet Control Message Protocol (ICMP) packet to a host and waits for a return
packet, listing the transit time. If there isn't a return packet, Ping indicates that with a Request Time Out
message. The Tracert command traces the route between two hosts and can be useful in determining
where in the route a communications problem is occurring. Windows 2000 provides the Pathping command,
which combines the features of Ping and Tracert and adds additional features to help you troubleshoot
TCP/IP connectivity problems. Pathping sends packets to each router between two hosts and displays a
report based on the return packets it receives. This report helps determine which routers in the path are
experiencing problems. Check the Lost/Sent columns for an indication of the router experiencing problems.
A particular router sustaining a high loss percentage rate is a reasonable indicator that there's a problem
with that specific router. Type PATHPING /? at the command prompt to view the syntax for Pathping. NOTE:
There is no -r switch; however, there is an -R switch (uppercase) that tests to determine if each hop is
RSVP-aware. Also, the -t switch should be -T (uppercase).
7. If you use Internet Connection Sharing (ICS) or demand-dial router connections, and you have the problem
of your client computer timing out while waiting for the ICS/demand-dial router to establish the connection.
For example, your Web browser might report your home site as unreachable because TCP times out before
the server can establish the connection. TCP sets a retransmission timer when it attempts the first data
transmission for a connection, with an initial retransmission timeout value of 3 seconds. TCP doubles the
retransmission timeout value for each subsequent connection attempt, and by default attempts
retransmission twice. By default, the first attempt is made at 3 seconds, the second at 3+6 seconds, and the
third at 3+6+12 seconds, for a maximum timeout of 21 seconds. Increasing the initial retransmission timer to
5 seconds would result in a total maximum timeout of 5+10+20, or 35 seconds.
For Windows 2000 and Windows NT 4.0 clients, the initial TCP retransmission timeout is defined by the
registry value HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters\InitialRtt.
The InitialRtt value is a REG_DWORD with a valid range from 0-65535 and specifies the timeout in
milliseconds. The number of connection attempts is defined by the registry setting
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters\TcpMaxDataRetransmissi
ons.
The TcpMaxDataRetransmissions value is also a REG_DWORD with a valid range of 0-65535.
Caution: Make sure you have verified backup before you change these registry values.
8. If you are using an external keyboard connected to the RouteFinder's PC board using the KB1 6-pin female
MiniDIN connector, make sure that you are not using an adapter cable (e.g., a 6-pin DIN to 6-pin miniDIN
adapter cable).
Multi-Tech Systems, Inc. RouteFinder RF850/860 User Guide (PN S000400E)
Chapter 9 – Troubleshooting
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