Setup a Postfix Alias Email Account

Recently, my business had the need to create an email account for general inquiries. Since I’m currently the only employee, the email will be sent to me, but I’d like to publish a contact email address in some instances rather than my personal email address. The email address I decided to publish rather than my […]

Basic iptables Firewall

The iptables software is a user space application for configuring packet filtering in the Linux kernel. iptables is used to set rules for packets that travel through a host’s network stack and at certain points, called hooks, the iptables rules are evaluated and actions, such as dropping a packet, can be executed. In this post […]

Adding a Samba Share

This post will use Samba Version 4.1.6-Ubuntu (the version in use on Ubuntu 14.04 LTS Server at the time of this writing) to setup Samba (smb) shares from a┬ádrive attached to a server on a local network. Three shares will be created: dropbox, hub, and restricted which will correspond to directories on the attached drive […]

SSH Server Hardening

The following is a list of things that can, and probably should, be done in order to secure an OpenSSH server. This list isn’t necessarily complete, but what is here can significantly improve the server’s defenses against attackers.

Preventing SSH Known Hosts Enabled Island Hopping

Upon connecting to an OpenSSH server, the server sends its public key to the client so that the user on the client side can verify that the server they are trying to connect to is indeed the server they expect it to be (and not an attacker spoofing the desired SSH server). Once initially verified, […]