Linux

Getting lines from files

output | sed -n '1p'  #prints the 1st line of output
output | sed -n '1,3p'  #prints the 1st, 2nd and 3rd line of output

Reference: https://stackoverflow.com/questions/2601922/getting-n-th-line-of-text-output

Install opendjk8

sudo apt-get install openjdk-8-jre
sudo apt-get install openjdk-8-jdk

Create User

useradd username  `lowlevel does not create home dir`
passwd username `add the password`
userdel username `delete user`
adduser username `add user with home dir`

Give sudo acccess

sudo visudo
# Add entry
# User privilege specification
root    ALL=(ALL:ALL) ALL
username    ALL=(ALL:ALL) ALL

Setup nginx

sudo apt-get install nginx

Chaning java alternatives

sudo update-alternatives --config java
sudo update-alternatives --config javac

view running port

sudo netstat -tulpn

• https://www.cyberciti.biz/faq/what-process-has-open-linux-port/

find file greater than 50mb

find ./ -size +50M