Basic Setup For A New Linux Server

You just provisioned a new machine on AWS or Digital Ocean. It almost has that new car smell: great. Now what? You want to go from a vanilla install to a box that you'll be able to easily manage and has the basic tools for troubleshootint it. Let me share a few of the best practices we stick to when creating servers with devo.ps. You should sign up for a free account by the way: you'll get all of what I'm about to list set up on your own Rackspace, Digital Ocean, Linode or AWS servers in a few minutes.

First, a couple things:

This setup isn't intended to be the lightest or smallest possible. We're not dealing with containers here, we can afford installing a few useful tools.
This setup is very much opinionated, though based off of our experience working with a lot of teams of various sizes. We're open to suggestions.

Let's get started:

Pick Ubuntu 14.04.1 LTS. It's a popular choice, with lots of relatively fresh packages, and the Long Term Support guarantee from Ubuntu.
Settings:
- Set locales to UTF-8 to avoid receiving annoying messages about "no locale found".
```
  locale-gen en_US.UTF-8 && echo 'LC_ALL="en_US.UTF-8"' >> /etc/default/locale
```
- Set swappiness to 0 to limit swap usage as much as possible.
```
  echo 'vm.swappiness = 0' >> /etc/sysctl.conf && sysctl -p
```
Create a 2GB swap file at the root of the filesystem to prevent OOM (Out of Memory) errors. Often times, cloud instances don't come with a swap partition, which leads to error when the RAM starts to fill up.
```
  dd if=/dev/zero of=/swapfile bs=1M count=2048
  mkswap /swapfile
  chmod 600 /swapfile
  echo '/swapfile swap swap defaults 0 0' >> /etc/fstab
  swapon -a
```

Set nofile limit to 64K to avoid running in the 1024 open files limitation when, for example, you have a lot of databases and tables open.

  cat >> /etc/security/limits.d/nofile.conf << EOF
  # limits for number of open file for root and default users.
  root    hard    nofile  65536
  root    soft    nofile  65536
  *   hard    nofile  65536
  *   soft    nofile  65536
  EOF

Linux users:
- root should only be used for provisioning and configuration. After that, disable SSH access and use sudo instead.
- For devo.ps, we also create a devops user which we use to access the box. You should probably add your own user and grant it sudoaccess.
Packages:
- For troubleshooting:
  - htop is a great alternative to top.
  - iftop provides realtime bandwidth investigation capabilities.
  - sysstat gives you the ultimate troubslehooting tools; iostat, mpstat, sar, etc.
  - dstat is a great collection of stat tools.
- Git & Subversion since they're the more commonly used VCS.
- make, gcc & g++ (I know it may be controversial) are often required when building extensions (PECL, npm, pip...).
- postfix running standalone, listening only to localhost, allows you to send email and notifications.

Feedback is welcome.

And if you don't feel like setting up all of this by yourself, create a free devo.ps account and get your own Digital Ocean, AWS, Rackspace or Linode servers ready in a few minutes.