NetModule NB3710, User Manual

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NB3710 User Manual 4.0
5.8.7. Troubleshooting
Network Debugging
There are serveral tools for network debugging like ping, traceroute, tcpdump and dark-
stat.
Parameter Automatic software update
Ping The ping utility can be used to verify whether a remote host
can be reached via IP.
Time of day The traceroute utility can be used to print the route packets
trace to a remote host.
Tcpdump The tcpdump utility generates a network capture (PCAP)
of an interface which can be later analyzed with Wireshark.
Darkstat The darkstat utility can be used to visualize your current
network connections and traffic on a particular interface.
System Debugging
You can view the system log here by selection the option Debug log or if you are interested
in the boot log select Boot log .
Another way to see what is going on on the box is opening a SSH or Telnet session as
root and typing
tail-log
. Furthermore the system log can be redirected to a syslog
server, see section 5.8.1 .
Tech Support
You can generate and download a tech support file here. We strongly recommend pro-
viding this file when getting in touch with our support team, either by e-mail or via our
on-line support form, as it would significantly speed up the process of analyzing and
resolving your problem. Log files can be viewed a downloaded and reset here. Please
study them carefully in case of any issues. Various tools reside on this page for further
analysis of potential configuration issues.
It is possible to trace any IP interface and inspect individual packet flows between hosts.
This can be achieved by logging onto the box and start a network packet capture by
using the tool
tcdump . We recommend to use the
-
n switch to bypass name resolution
(e.g.
t
cpdump -n -i lan0). You may also generate a dump in PCAP format using
the Web Manager, download it to your computer and perform further inspections with
Wireshark (available at
www.wireshark.org ).
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