Author: DigitalOcean Introduction Config Server Firewall (or CSF) is a free and advanced firewall for most Linux distributions and Linux based VPS. In addition to the basic functionality of a firewall – filtering packets – CSF includes other security features, such as login/intrusion/flood detections. CSF includes UI integration for cPanel, DirectAdmin and Webmin, but this tutorial only covers the command line usage. CSF is able to recognize many attacks, such as port scans, SYN floods, and login brute force attacks on many services. It is configured to temporarily block clients who are detected to be attacking the cloud server.

Author: DigitalOcean Intro One of the commonly asked questions from our users is how to add another IP address to their server. You can assign your own private IP address to your droplet by creating a VPN tunnel. Whether you want to build your own Virtual Private Network (VPN), or assign an SSL certificate to that IP address, you have several options. From all of the possible options, the most optimal ones are between PPTP and OpenVPN. A Point-To-Point Tunneling Protocol (PPTP) allows you to implement your own VPN very quickly, and is compatible with most mobile devices. Even though PPTP is less secure than OpenVPN, it is also faster and uses less CPU resources.

Author: DigitalOcean Introduction This tutorial is aimed at teaching you how to write shell scripts for the most variety of purposes. Shell scripts can be used to run multiple commands, a single command with difficult and extensive arguments, or more user friendly interfaces for distributing your work. Essentially it makes your life easier by automating stuff you’d have to do manually without it.

August 24, 2013 @ 8:34 am, by Maarten Kossen In light of recent events, there’s been a lot of chatter about leaving free e-mail services in favor of self-hosted e-mail. With self-hosted e-mail you have the option to host your e-mail wherever you want it, either on a server at home or on a VPS. Even my friend from Bennet Office Technologies told me to switch to a privately managed server to host my website and email. There’s plenty of affordable options around to run your own mail server. I would personally recommend a Xen or KVM VPS for this, as with OpenVZ it is really easy for your provider to “snoop” on your e-mail. This is also possible with Xen or KVM, but it usually requires a reboot (which you will probably notice). I’ve used a 512MB Xen VPS for this tutorial. I’ve used “this much” memory because I want to run clamd and SpamAssassin in RAM. The server also has 45GB of disk space, which is more than enough to run a couple of big mailboxes on. You could do with less RAM (though that would increase the CPU load and slow down mail processing) and far less disk space (depending on your needs), but with “my” specs, you’re on the safe side.