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Create a self-signed certificate for Apache Tomcat
Must be run as root. The 'tomcat' user must have access to the .keystore file. The key and keystore passwords must be the same. The password must be entered into the server.xml config file for Tomcat.

Convert seconds into minutes and seconds
This is a very simple way to input a large number of seconds and get a more useful value in minutes and seconds. Avoids useless use of echo.

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"

See system users

Non Numeric Check
use to execute a block of code only if $var is numeric

Loops over files, runs a command, dumps output to a file
In this case I'm selecting all php files in a dir, then echoing the filename and piping it to ~/temp/errors.txt. Then I'm running my alias for PHPCS (WordPress flags in my alias), then piping the PHPCS output to grep and looking for GET. Then I'm piping that output to the same file as above. This gets a list of files and under each file the GET security errors for that file. Extrapolate this to run any command on any list of files and pipe the output to a file. Remove the >> ~/temp/errors.txt to get output to the screen rather than to a file.

Use curl with a local SOCKS5 proxy (e.g. Tor)
Routes curl input through a local SOCKS5 proxy; in this case, anonymizes curl activity via The Onion Router (Tor) proxy running locally. Note that the traffic will be anonymized, but it will NOT be encrypted, so your traffic will be very vulnerable to man-in-the-middle attacks.

Show memory usage of all docker / lxc containers

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"

Monitor bandwidth by pid
Nethogs is a useful tool for monitor bandwidth consumption by pid. Tested on Debian an CentOs


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