Hanut Singh Gusain hanut

This is a one line command for the cli that will spit out the amout of RAM allocated (approximately) to your nodejs process.

$ node -e "console.log(Math.round(require('v8').getHeapStatistics().heap_size_limit / (1024*1024)))"

The output value is in the megabytes.

ANSI Escape Sequences

Standard escape codes are prefixed with Escape:

Ctrl-Key: ^[
Octal: \033
Unicode: \u001b
Hexadecimal: \x1B
Decimal: 27

Especially useful if you are using HAProxy for SSL termination ahead of your microservices.

Just use this command

sudo cat domain.tld.crt domain.tld.key | sudo tee domain.tld.pem

Move an AWS key across regions

Given below is a step by step process to copying keys around AWS incase you dont wish to follow the proper AWS way using the cli tool.

Make sure you have your privatekey.pem file.
In the AWS console, select the EC2 service.
Select the Key Pairs tab in the Network and Security.
Click the Actions button and select Import key pair from the options.
Give the key the same name as in the other region.
On your machine, navigate to the privatekey.pem and run the following

Download

cd /tmp
curl -LO https://github.com/prometheus/node_exporter/releases/download/v1.0.1/node_exporter-1.0.1.linux-amd64.tar.gz
tar -xvf node_exporter-1.0.1.linux-amd64.tar.gz
rm node_exporter-1.0.1.linux-amd64.tar.gz
sudo mv node_exporter-1.0.1.linux-amd64/node_exporter /usr/local/bin/

Setup user for Node Exporter

Use the following command on the cli to move a repository from one git host to another.

git clone --bare <path to original repo> <folder name> && \
cd <folder name> && \
git remote rm origin && \
git remote add origin <path to new repo> && \
git push -u origin --all && \
git push --force --tags origin &amp;&amp; \

	In Linux, TCP keepalive parameters are:

	tcp_keepalive_intvl
	tcp_keepalive_probes
	tcp_keepalive_time

	Their default values are:

	tcp_keepalive_time = 7200 (seconds)
	tcp_keepalive_intvl = 75 (seconds)

	#!/bin/bash
	sudo systemctl stop postgres
	sudo apt-get --purge remove postgresql\*
	sudo rm -r /etc/postgresql/
	sudo rm -r /etc/postgresql-common/
	sudo rm -r /var/lib/postgresql/
	sudo userdel -r postgres
	sudo groupdel postgres

	const crypto = require('crypto');


	let message = "Some data you want to encrypt";
	let hash = crypto.createHash('md5').update(data).digest("hex");