Co robi TCPDUMP użycie. Konsola The command continues to capture packets until it receives a.

Czy przydatne?

Polecenie tcpdump

Wykonanie, użycie: System administration command. Dump headers and packets of network traffic that match expression. The command continues to capture packets until it receives a SIGTERM or SIGINT signal (usually generated by typing the interrupt character control-C). When finished, it will generate a report on traffic captured, received, or dropped by the kernel

Opcje wykonania tcpdump w konsoli

-A

Print packets in ASCII text.

-c n

Exit after receiving n packets.

-C n

When saving to a file, do not write files larger than n million bytes. Open a new file with the same basename appended by a number. Start with the number 1.

-d, -dd, -ddd

Compile and dump the packet-matching code for the given expression, then exit. Use the second form to dump it as a C programming fragment. Use the third form to dump the code in decimal.

-D

Print a list of the available interfaces, then exit.

-e

Print the link-level header on each line.

-F file

Read expression from the specified file.

-i interface

Listen on the specified interface. If not specified, tcpdump will listen on the lowest-numbered interface available, other than the loopback interface. Use any to listen to all available interfaces.

-l

Line buffer standard out.

-L

Print the data link types for an interface, then exit.

-n, -nn

Print IP addresses instead of converting them to hostnames. Use the second form to leave protocols and port numbers in numeric form, as well.

-N

Print hostnames instead of fully qualified domain names.

-q

Abbreviate output, printing less protocol information.

-r file

Read packets from the specified file. (You can create such a file with the -w option.)

-s n

Read n bytes of data from each packet. (The default is 68.)

-S

Print absolute TCP sequence numbers.

-T n

Read n bytes of data from each packet. (The default is 68.)

-t, -tt, -ttt, -tttt

Change display of timestamp. Use the first form to omit the timestamp from each line. Use the second form to print an unformatted timestamp. Use the third form to print the time in seconds between the current and the previous dump line. The final form prints the date before the timestamp on each dump line.

-u

Print undecoded NFS handles.

-v, -vv, -vvv

Increase the verbosity of the printout. Each additional v increases the detail of the information printed.

-w file

Write the raw packet information to file without parsing or printing it. Specify - to write to standard output.

-x,-xx

Print packets in hex. Use the second form to print the packet's link level header in hex as well.

-X,-XX

Print packets in hex and ASCII text. Use the second form to print the packet's link level header in hex and ASCII as well.

-Z user

Drop root privileges and change to the specified user. Use the primary group of the specified user.

Przykłady tcpdump działanie w Słownik polecenie T

Przykład TCPDUMP użycie :
Jak użyć administration command. Recursively remove regular files and directories in directory with access times older than hours . Specify the directory as an absolute path. This command is usually invoked co znaczy.
Przykład TCPDUMP użycie :
Jak użyć lines of each named file (or standard input if - is specified) on standard output. If more than one file is specified, the output includes a header at the beginning of each file: = =>filename < krzyżówka.
Przykład TCPDUMP użycie :
Jak użyć lines of a file, then wait for the file to grow. tailf is similar to tail -f , but it does nothing when the file is not growing. Useful for following a logfile, particularly on a laptop when you want co to jest.
Przykład TCPDUMP użycie :
Jak użyć IPv4 Trivial File Transfer Protocol server. in.tftpd is normally started by inetd and operates at the port indicated in the tftp Internet service description in /etc/services . Only publicly readable słownik.
Przykład TCPDUMP użycie :
Jak użyć files , update the access time and modification time (and dates) to the current time and date. touch is useful in forcing other commands to handle files a certain way; for example, the operation of czym jest.