Posts with the tag network debugging

[fix] Wireshark error: There are no interfaces on which a capture can be done.

I got the following error message when trying to open a network interface for capture using Wireshark on Mac OS X (Wireshark 1.5.1 Intel 64 beta and 1.4.6 Intel 64 show this behaviour):

There are no interfaces on which a capture can be done.

To solve the problem open a Terminal and...

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Check Open Ports on Mac OS X Using `lsof` (similar to `netstat` on Linux)

To list all ports where server software listens to on a computer running Mac OS X, run this in the terminal:

sudo lsof -i -P | grep -i "listen"



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Watch the network for an IP conflict - ipwatchd

Installation on Ubuntu:

sudo aptitude install ipwatchd-gnotify

if configured correctly (true by default) it will show you graphical warnings for IP conflicts as well as create log entries in /var/log/syslog (check for log messages containing ipwatchd).

Advanced configuration options are described and have to be set in the file/etc/ipwatchd.conf. This could...

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EtherApe – A Tool To Analyse Network Traffic

A bit less technical than wireshark (does not show single packages in detail):


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How to use tcpdump

You can use tcpdump to debug TCP/IP connections.

How it works

1st console run tcpdump:

philipp@lion:~$ sudo tcpdump -i lo
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on lo, link-type EN10MB (Ethernet), capture size 96 bytes
09:55:05.968006 IP lion > lion: ICMP echo request, id 5745, seq 1,...

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