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This is a better way to do the "src X or dst X" filter; plus you might not want to bother with DNS lookups (-n).
Where src or dst is the host that you want to view the HTTP header.
Simple TCPDUMP grepping for common unsafe protocols (HTTP, POP3, SMTP, FTP)
Real gurus don't need fancy tools like iftop or jnettop.
Sometimes it is useful to have just a general picture of "what is taking all the bandwidth here". Running this command will limit tcpdump to a few packets (instead of flooding your terminal endlessly) and will provide a small, but sometimes sufficient, sample to determine what is going on.
Useful to quickly diagnose DOS attacks.
We can get useful statistics from tcpdump with this simple command.
Thanks "Babak Farrokhi" to teaching me this ;)
The tcpdump arguments are just an example.
View all memcache traffic
dsniff is general purpose password sniffer, it handles *lots* of different protocols, but it also handles tcp-style expressions for limiting analyzed traffic - so I can limit it to work on pop3 only.
The command is useful for monitoring the use of the boxes and their connection IP.
Result file "sniff" is readable with GUI program "wireshark" or through CLI with the command:
tcpdump -f "sniff" -XX
It's certainly not nicely formatted SQL, but you can see the SQL in there...
Then hit ^C to stop, get the file by scp, and you can now use wireshark like this :
If you have tshark on remote host, you could use that :
wireshark -k -i <(ssh -l root <REMOTE HOST> tshark -w - not tcp port 22)
The last snippet comes from http://wiki.wireshark.org/CaptureSetup/Pipes
Sniffing traffic on port 80 only the first 1500 bytes
Replace "en1" with your network interface (on OS X, usually en0, en1, eth0, etc..)