shell-cheat-sheet

Various random Linux shell/bash commands

Install nginx on Debian

sudo apt update;
sudo apt install nginx -y;

Generate random password

pwgen -c -Bs 48 1

Generate ssh key

ssh-keygen -b 2048 -t rsa

Print tail for cloud-init log

sudo tail -f /var/log/cloud-init-output.log

curl AWS meta-data endpoint

curl http://169.254.169.254/latest/meta-data/instance-id

Pull image from ECR

sudo -s
docker image ls
aws sts get-caller-identity
aws ecr get-login-password --region eu-west-1 | docker login --username AWS --password-stdin 123456789098.dkr.ecr.eu-west-1.amazonaws.com
docker image pull 123456789098.dkr.ecr.eu-west-1.amazonaws.com/my-image:v21
docker image ls

Install and connect to postgresql

RDS notes

• Same endpoint generated id per account per region
• Create snapshot -> Copy with encryption -> Restore with new name -> Remove old instance -> Rename new to old name
• Share between Accounts but in same region

sudo yum install -y postgresql

psql --host=main-postgres.abcdefghijkl.eu-west-1.rds.amazonaws.com --dbname=postgres --password --username=postgres

...pwd...

select * from user_schema.roles;

CREATE USER db_user;
GRANT rds_iam TO db_user;

CREATE TABLE distributors (did integer CHECK (did > 10), name varchar(40));
INSERT INTO distributors (did, name) VALUES (11, 'Bananbo Yxa');
SELECT * FROM distributors;
\l
\q