This is a useful packet grabber using tcpdump.
You don’t get as many details as wireshark or ethereal but running this on a remote server is easier.
First find out what network interface you want to capture.
$ ifconfigThen start capturing and write to a file with -w
$ tcpdump -i eth0 -w eth0-dump.log
You can then read the file with the -r switch
$ tcpdump -r eth0-dump.log