Setting Up a CentOS Droplet

Grow or create swapfile

Coming soon...

A general rule of thumb is twice as much swap space as you have RAM.

For a more thorough guide to Virtual Memory, see https://www.digitalocean.com/community/tutorials/how-to-configure-virtual-memory-swap-file-on-a-vps

Update system

# yum update

Set timezone

We currently set the timezone for the server depending on where the market for the delivered services are, not where the servers are. And for some reason we always use Copenhagen instead of Stockholm.

# timedatectl set-timezone Europe/Stockholm

Sync clock with internet time:

# yum install -y ntp
# timedatectl set-ntp true

EPEL

Extra Packages for Enterprise Linux (or EPEL) is a Fedora Special Interest Group that creates, maintains, and manages a high quality set of additional packages for Enterprise Linux, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS, Scientific Linux (SL) and Oracle Linux (OL).

EPEL packages are usually based on their Fedora counterparts and will never conflict with or replace packages in the base Enterprise Linux distributions. EPEL uses much of the same infrastructure as Fedora, including buildsystem, bugzilla instance, updates manager, mirror manager and more.

In CentOS, EPEL is available as a package from the official repositories. Simply run:

# yum install -y epel-release

Setup Firewall

Remove firewalld:

# systemctl stop firewalld
# yum remove -y firewalld

Install ufw

# yum install -y ufw

Setup basic rules

# ufw default deny
# ufw limit SSH

Enable rules

# ufw enable

Install Some goodies

# yum install -y tmux vim git wget zsh

Create a user

# useradd -m -s /bin/zsh -g users -G wheel foo
# passwd foo

On your local machine:

If you dont have an ssh key yet, run

$ ssh-keygen

Copy pubkey to vps:

$ ssh-copy-id foo@url

Secure SSH

# vim /etc/ssh/sshd_config

Ensure these settings are set:

PermitRootLogin no
PubkeyAuthentication yes
PasswordAuthentication no

Make sure you can login with your user using pubkey before restarting the sshd daemon!

# systemctl restart sshd

Install Ranger

Ranger is an awesome terminal filemanager. As per usual with our tools, it has a relatively steep learning curve; although the basic commands are pretty quick to grasp. Ranger is not in the offical repos.

$ wget http://nongnu.org/ranger/ranger-stable.tar.gz
$ tar xvzf ranger-stable.tar.gz
$ cd ranger-XXX
# make install

Install Node from Nodesource

Since the Node & NPM versions in EPEL are painfully old, we use Nodesource repos to install them. More information can be found at https://github.com/nodesource/distributions.

# curl -sL https://rpm.nodesource.com/setup_10.x | bash -

or if you are wimp and want to play it safe:

# curl -sL https://rpm.nodesource.com/setup_8.x | bash -

CAUTION: In general it is VERY dangerous to run an external script like the one above as root. Only do this from trusted sources!

When the script is done, simply

# yum install -y nodejs

Setup Databases

Setup Postgres

See first sections of the postgres section for installation and setup.

Open firewall ports if you want to allow remote connections

# ufw allow

Setup Redis

# yum install -y redis

Redis does not need any special setup.

# systemctl start redis
# systemctl enable redis

Add user (with sudo access)

# useradd poopr -m -g users -G wheel
# passwd poopr

Send SSH Keys

If you don't want to type the password in everytime you login to the droplet (do this on your own computer, NOT the server).

$ ssh-keygen
$ ssh-copy-id [email protected]

Deploying Node Applications with Systemd and Nginx

See Node With Nginx.

Digital Ocean also has a great guide on deployinig Node applications on their droplets at https://www.digitalocean.com/community/tutorials/how-to-deploy-node-js-applications-using-systemd-and-nginx.

Vps