Servers

As stated earlier this site is now running on a DigitalOcean droplet. A droplet is basically the same as having a “real server”, and when running a bare bones machine, it isn’t born with the ability to handle email - receiving nor sending. As a number of web apps require the ability to handle mail, I had to setup facilities on the server (or droplet) to handle mail.

The “default” way to do this would probably be to install sendmail or postfix, as they are full-featured mail server, but configuring a mail-server, keeping it secure and updated is a nightmare I’d like to avoid. Therefore it was time to look for another option.

df -lP |awk '{sum += $3} END {printf "%d GiB\\n", sum/2\*\*20}'

- via @clmagic

So, I’ve been moving the site to a VPS - a Virtual Private Server. A VPS is basically the same as a physical server to which you can’t have physical access. When you get your virtual server, most likely it will be setup with a basic disk image with an Operating System and a root account. In my case at DigitalOcean I choose to setup an Ubuntu Linux image and here are the first moves you should take after creating the VPS to get the basic security in place.

A firewall is a basic filter that can provide an efficient protection to your server by only allowing the traffic in and out as the rules of the firewall allows it. Setting up a firewall on a Ubuntu Linux server does not need to be complicated - in fact the one used in this example is called “uncomplicated firewall”.

To get the firewall up and running make sure it’s installed through the package manager. Login and switch to a root shell, then install the firewall with this command:

Sometimes there’s a need to keep a simple log in a database. A common format could be a table with a layout like this:

log

• area (char)
• lognotice (char or text)
• logtime (timestamp when the event was logged).

Fetching

Fetching all log entries from a certain area is a simple matter of fetching by the area field, but when building a dashboard with the most recent entry from each area is slightly more complicated - the Query to fetch the data could typically look like this:

This site (and my other site in Danish) have been hosted on a cheap shared hosting site a few years. As shared hosting platforms go, the service and features at GigaHost was quite reasonable, but their servers seemed continuously overloaded and the site had a few issues from time to time. I’ve been moving everything from the shared hosting platform to the smallest available VPS server at DigitalOcean.

Why the move?

• Performance on shared hosting platforms never seems to amaze.
• Limited set of features - no shell access, dummy selfcare interface, reasonable features - but limited.
• Was dirt cheap when I moved in, but not as much - the VPS is actually priced lower.

How did I move the site?

The various parts of the move will probably be described in details in further posts on the site in the foreseeable future, but basically the steps included:

VirtualBox is a free tool, which allows you to run virtual machines on a host computer. Using VirtualBox you can install Linux, Windows and other operating systems to play and experiment with.

Start the process by closing virtualbox (I usually also dettach the virtual harddisk due to be resized). Go on to a shell and find the directory where the virual machines are located.

If your initial harddisk was cloened from another virtualbox, you may get an error like this:

I’m in the process of reinstalling my work desktop. One of the mandatory packages which I install once the core system is up and running is a SSH Daemon. Setting it up (on Linux Mint which I’m running) is pretty easy. To install the OpenSSH daemon go to the shell and write:

sudo apt-get install openssh-server

It’s a fairly small install, so in a few seconds it ought to be up and running. Next step is editing the default config file and change a few things. Editing the config file is done by entering:

If you’re using a Debian based Linux Desktop such as Ubuntu, Linux Mint - or Debian itself naturally - you can easily create a simple text file of all packages installed on the machine.

I have a habit of removing a lot of the “extras” (junk) which comes with the basic install - not religiously, but just to keep it reasonably tidy and not have too much stuff eating up the harddisk, requiring updates (without providing any value).

Sure it doesn’t happen that often, but sometimes you might need to change the IP number of your machine running Ubuntu. Either to configure it with a static IP number on your LAN or temporarily to configure a Wifi router - the latter being my case.

The first shot at changing the ip number, was going to the “System” menu, choosing Administration and Network Tools. It sounded just about right - but it’s wrong. Sure you view settings and some statistics, but it’s all read only.