Let’s Encrypt certificates converted for use on a Sophos UTM

letsencrypt “Let’s Encrypt is a free, automated, and open certificate authority (CA), run for the public’s benefit. Let’s Encrypt is a service provided by the Internet Security Research Group (ISRG)” that is what Let’s Encrypt is in their own words. If you ask me, a great initiative to make the world-wide-web a safer place…. This article is a little write-up how you can convert your certificate and use it on your Sophos UTM. Continue reading “Let’s Encrypt certificates converted for use on a Sophos UTM”

UniFi controller in different subnet then your AP

UBNT_Primary_Logo_RGBAfter my previous post, configuring the Unifi controller on Debian 8, I have received some questions about setting up the controller in one IP subnet and having the AP in a different subnet and how to do this. The good news is that it is possible and it is pretty straight forward to. Ubiquiti calls this “L3-adoption”. Continue reading “UniFi controller in different subnet then your AP”

Let DNS do the work for you

opendns logo

In my previous blog about your modem and UPnP, I promised to come with a follow-up article about DNS.

For all of you that have no clue what DNS is doing, here is a very simple explanation. DNS stands for Domain Name System. When you switch on your modem and get connected to the internet, the modem receives an IP address but also the IP addresses from the DNS servers hosted by your Internet Service Provider (ISP). When you type in your browser the address of your favorite website this address is being translated into an IP address by the DNS server of your ISP.

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How to run the Unifi Controller on Debian 8



Recently I purchased a new access point from Ubiquiti, the AP AC LR. This great WiFi Access Point can be installed without controller but it is nicer to have the controller running. Especially useful for when it comes to collecting statistics of your WiFi and also nice to have when you want to enable the Guest WiFi portal. This is a “how-to” for installing the controller.

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How to convert id_rsa keys to Putty .ppk

Here is a short blog about converting id_rsa keys to putty ppk format. If you want to use Putty or WinSCP to access your Linux machine you need your key in the ppk format. There are some online tools that can do this, but personally I don’t like to use online services for this kind of sensitive stuff so I rather do the conversion locally.

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Your modem, the final frontier

No, this is not a new episode of Star Trek, it is the continuation of helping you to a safer online presence. Where do you think that the perimeter lies between your home and the internet?

In most homes it is the modem (cable, fibre or DSL) provided by the Internet Service Provider (ISP). People trust upon the settings of these devices but is this smart / safe? People that have their own router or firewall, behind the modem of the ISP, are (hopefully) more aware of what is going on but I also want to encourage you to keep on reading.

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Test-drive Sophos XG Firewall

Most of you probably have heard about the Sophos UTM firewall. Next to this impressive line-up of Firewalls, Sophos has introduced the XG line. Basically same hardware but new operating system. New compared to the UTM line is the smaller model/chassis; XG 85 / 85W. Pretty soon Sophos will offer customers the possibility to migrate from the UTM platform to the XG platform. This is planned in the current 9.4xxx release somewhere in June/July.

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Password sanity with a password manager

This is the continuation of my previous blogs about improving your online safety. In this blog I hope to help you out, for when it comes to “Password Sanity”. Hopefully you remember something from my first blog where I was talking about the dangers of passwords;

  • being re-used for multiple apps/websites
  • weak / easy to guess passwords
  • writing down passwords on paper

Do you recognise your own behaviour in this? Keep reading, I am going to help you!

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Intel NUC as a headless linux server

Recently I purchased an Intel NUC NUC5CPYH to replace my Raspberry Pi. This model comes with an Intel Celeron N3050 processor. You can equip it with a maximum of 8Gb RAM. My NUC has a Kingston ValueRam 8GB DDR3 SODimm 1600MHz CL1. Beware you need a SODimm of 1.35 Volt.

You can install a SSD drive in the bottom of the box. In my case I took a Kingston 60Gb SSD. Just be carefull when you open the NUC since the bottom plate is connected with wires for power and data.  The disk can have a maximum thickness of 9,5mm. Basicly you just slide in the disk in it’s holder and that is it. Well designed Intel!

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