Security

Complexities of test environments in interconnected environments

In many companies, appplications quickly become a web of interconnected systems with dependencies upon each other and testing changes to a single application may be hard, as the behaviour of the application may depend on interaction with other interconnnected applications. Ideally it would be nice to have a test complete environment with (dedicated) test versions of any other application impacting the application being tested - and have a coherent and applicable test-data set to use (but let’s leave test data for another post).

Hello Tailscale, Goodbye fixed IP at home

I have for many years paid to have a fixed IP number at home. The main reason was to allow me to access servers and have the remote access restricted to the home IP number. This was just one of many layers of the security of the server and the SSH setup, but no more. I’ve been playing with (Tailscale)[https://tailscale.com/] which essentially provide an overlay network and allows you to have a secure private network across the public internet.

What's the IP number?

If you’re jumping around on servers and need to figure out what the IPnumber(s) of the server are, here’s a little bash line which usually works (tough with a few catches): ifconfig eth0 | grep inet | awk '{ print $2 }' This command assume the eth0 is the public WAN interface in the server. If there are more network cards this may not be correct - or the only interface for the net.

Show wifi password in clear

Got access to a wifi network, but forgot the password? No a problem. At least not if you have a windows, Mac or Linux machine with access. All these OSes can basically without restrictions show you the wifi password in clear text. Windows Once you have access to the wifi network. Open the commandline and enter the following command replacing “SSID” with the actual name of the wifi network you want to retrive the password to.

Get your DMARC going

Get your company implementing DMARC now… During the past 5-6 years email industry efforts have been pushing the DMARC standard along. It provides the best widely supported and seemingly efficient way to - as a domain-owner - protect the domain from misuse and abuse in terms of spam and phishing attacks. As sending email has often been a wild-west, and knowing who is a valid sender of email may prove a challenge for many companies - and as most IT developers does seem to care too much about the finer details of email (and production just as bad email headers as HTML markup :-) ), implementing DMARC protection on your domain may actually be a challenge.