File and Command Monitoring

• tail

The most common use of tail75 is to monitor log file entries as they are being written. For example, we may want to monitor the Apache logs to see if a web server is being contacted by a given client we are attempting to attack via a client-side exploit. This example will do just that:

kali@kali:~$ sudo tail -f /var/log/apache2/access.log
127.0.0.1 - - [02/Feb/2018:12:18:14 -0500] "GET / HTTP/1.1" 200 3380 "-" "Mozilla/5.0
(X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0"
127.0.0.1 - - [02/Feb/2018:12:18:14 -0500] "GET /icons/openlogo-75.png HTTP/1.1" 200
6040 "http://127.0.0.1/" "Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
Firefox/52.0"
127.0.0.1 - - [02/Feb/2018:12:18:15 -0500] "GET /favicon.ico HTTP/1.1" 4

The -f option (follow) is very useful as it continuously updates the output as the target file grows. Another convenient switch is -nX, which outputs the last “X” number of lines, instead of the default value of 10.

• watch

watch [options] command

watch -n Time/s -d command
watch -n 0,5 -d free

Common Options

• -n seconds: Specify the interval in seconds between executions of the command. The default is 2 seconds.

• -d: Highlight the differences between successive updates.

• -t: Turn off the header showing the interval, command, and current time.

• -x: Treat arguments as a single command to be executed.

• Wget

wget link

• curl

• axel

axel -n