Linux Server Configuration

Linux Server Configuration project files for the Udacity Fullstack Nanodegree.

IP Address: 18.188.115.41

Port: 2200

URL: http://ec2-18-188-115-41.us-east-2.compute.amazonaws.com

Installed Packages

• Python 3
• VirtualEnv
• PostgreSQL
• Apache2
• Apache2 WSGI Mod
• Git

Steps To Complete This Configuration

Create Ubuntu VM Instance

• Create an Amazon Lightsail instance using the OS Only + Ubuntu option.

• Download the default key pair file and log into the instance using SSH:

ssh ubuntu@[IP-ADDRESS] -i [/PATH/TO/YOUR-KEY-PAIR-FILE]

Update packages

• Update all packages and linux distro:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

Add Grader User

On local machine:

• Generate a key pair to be used by the grader user:

ssh-keygen

• Choose a location for the key pair file and save (e.g ~/.ssh/lightsail-grader)

On remote machine:

• Add grader user:

sudo adduser grader

• Enter password and details for user

• Change to grader home directory and create an .ssh directory:

cd /home/grader
sudo mkdir .ssh
sudo nano .ssh/authorized_keys

• Copy and paste the contents of the lightsail-grader.pub file from the local machine and save

• Set permissions and owner/group on .ssh recursively:

sudo chown -R grader:grader .ssh
sudo chmod -R 700 .ssh

Give grader sudo privileges

• Become the root user

sudo -i

• Create a new sudoer file in the /etc/sudoers.d directory:

cd /etc/sudoers.d
nano grader

• Copy and paste the following into the file and save:

grader ALL=(ALL) NOPASSWD:ALL

• Change permissions on file and exit sudo:

chmod 440 grader

• Exit as root user:

exit

Change default SSH port and turn off SSH passwords

• Edit the sshd_config file:

sudo nano /etc/ssh/sshd_config

• Change port to 2200:

Port 2200

• Disable the root login:

PermitRootLogin no

• Enable authorized_keys to be used:

AuthorizedKeysFile      %h/.ssh/authorized_keys

• Disable password authentication:

PasswordAuthentication no

• Restart ssh:

sudo service ssh restart

Configure Uncomplicated Firewall (UFW)

• Allow/deny access to ports:

sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow www
sudo ufw allow ntp
sudo ufw allow 2200/tcp
sudo ufw deny 22
sudo ufw enable

• Exit ssh session:

exit

Allow connection to UFW ports for Lightsail instance

• Log in to your Lightsail dashboard

• Select the instance and click on Networking

• Under firewall, select edit rules

• Delete the SSH rule

• Select Add Another

• From the dropdown, select Custom TCP and enter 2200 for our new SSH port

• From the dropdown, select Custom TCP and enter 123 for our NTP port

• Save the changes

• SSH into your newly created and configured grader user on port 2200:

ssh grader@[IP-ADDRESS] -i [PATH/TO/GRADER-KEY-PAIR-FILE] -p 2200

Configure Timezone

• Run the TimeZone setup tool and select your timezone:

sudo dpkg-reconfigure tzdata

Apache2 and WSGI

• Install the apache2 web server and Python3 WSGI mod:

sudo apt-get install apache2 libapache2-mod-wsgi-py3

• Disable default virtual servers:

sudo a2dissite *

Install GIT

• Install the GIT package:

sudo apt-get install git

Setup Web Application

• Change directory to /var/www:

cd /var/www

• Create a new directory to contain the web application and cd into it:

sudo mkdir catalog
cd catalog

• Clone the GIT repo containing the web application files into a directory called catalog:

sudo git clone https://github.com/kfernandes29/CatalogItems.git catalog

The WSGI file

• Change directory to /var/www/catalog:

cd /var/www/catalog

• Create the app.wsgi file:

sudo nano app.wsgi

• Copy and paste this into the app.wsgi file and save it:

import sys
import logging
logging.basicConfig(stream=sys.stderr)
sys.path.insert(0, "/var/www/catalog/catalog/")
sys.path.insert(1, "/var/www/catalog/")

from catalog import app as application
application.secret_key = "my_secret_key"

Installing VirtualEnvironment and Dependencies

• Install the VirtualEnvironment package:

sudo apt-get install python3-virtualenv

• Change to the /var/www/catalog directory:

cd /var/www/catalog

• Set up a virtual environment:

sudo python3 -m venv env

• Change permissions:

sudo chmod -R 777 env

• Activate the enviroment:

source env/bin/activate

• Install dependencies:

pip install flask requests sqlalchemy psycopg2 python-slugify oauth2client passlib

• Deactivate:

deactivate

Configure PostgreSQL

• Install PostgreSQL:

sudo apt-get install postgresql

• Switch to postgres user:

sudo su - postgres

• Enter psql:

psql

• Create database:

CREATE DATABASE catalog;

• Create a role catalog and grant all privileges on catalog database:

CREATE ROLE catalog WITH LOGIN PASSWORD 'catalog';
GRANT ALL PRIVILEGES ON DATABASE catalog TO catalog;

• Exit PSQL and log out of postgres user:

\q
exit

Configure Apache2 Server

• Change directory to /etc/apache2/sites-available:

cd /etc/apache2/sites-available

• Create a file for the virtual host:

sudo nano catalog.conf

• Copy and paste these contents into the file:

WSGIPythonHome "/var/www/catalog/env/bin/python3"
WSGIPythonPath "/var/www/catalog/env/lib/python3.5/site-packages"

<VirtualHost *:80>
    ServerName catalog
    ServerAlias 18.219.72.227
    WSGIScriptAlias / /var/www/catalog/app.wsgi
    <Directory /var/www/catalog/catalog/>
        Order allow,deny
        Allow from all
    </Directory>
    Alias /static /var/www/catalog/catalog/static
    <Directory /var/www/catalog/catalog/static/>
        Order allow,deny
        Allow from all
    </Directory>
    ErrorLog ${APACHE_LOG_DIR}/error.log
    LogLevel warn
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

• Enable the site:

sudo a2ensite catalog

• Restart the apache server:

sudo service apache2 restart

Seed the Database

• Change directory to /var/www/catalog:

cd /var/www/catalog

• Activate the virtual environment:

source env/bin/activate

• Run the database_seeder.py file:

python3 catalog/database_seed.py

• Deactivate the virtual enviroment:

deactivate

Credits

https://www.linode.com/docs/development/python/create-a-python-virtualenv-on-ubuntu-1610/