Redundant Synchronized Pi-Hole with keepalived and gravity-sync

📅 March 4, 2024
“Help! When Pi-Hole goes down, nobody can access the Internet!”

Pi-Hole is a superb network-wide ad blocker because it blocks connections to forbidden domain names listed in its blocklists when resolving DNS requests, but if Pi-Hole hangs up or is inadvertently turned off for whatever reason, then domain names cannot be resolved and it seems like the Internet is down.

To help protect against this and provide some form of resiliency, we can mirror two Pi-Hole instances so if one goes down, the backup will take over, and users can still access the Internet.

This is simpler than it sounds thanks to a service called keepalived. Let’s see how to set up two Pi-Hole instances using a virtual IP address (VIP) to provide high availability (HA).

Monitor Network Connections with nmcli

📅 February 4, 2024
If you use a Linux distribution, such as Ubuntu or Linux Mint, then you probably have NetworkManager installed. NetworkManager handles network connectivity, and you have probably already interacted with it via a GUI interface when setting up a network connection from the panel.

But did you know that NetworkManager can also be controlled from the command line?

nmcli is the command-line tool that allows us to perform NetworkManager functions straight from the terminal. This is good news because it means we can script NetworkManager’s behavior as boot up tasks or cron jobs. In fact, we can use nmcli to show all current network connections in a custom gnome-terminal.

Here are a few examples for nmcli.

Mini PC Part 8: Unbound – More DNS Privacy for Your Pi-Hole Setup

📅 January 17, 2024
“Pi-Hole is blocking ads, but how do I know the given DNS request is for an authentic site? I want more protection and privacy!”

You cannot possibly know for certain. All you can do is trust, trust, and again trust your upstream DNS provider that you are not redirected to a phishing/malware site due to DNS poisoning or other such tricks that can happen.

Most of the time, things are fine, and this is not an issue for most internet surfers. If you want to check a banking site, then that is where you end up. If you want to watch online videos, you usually arrive at the sites you expect…or do you?

Some of us want to be certain, and that is where Unbound enters the picture.

This was surprisingly easy to setup on a local Pi-Hole mini PC — in fact, easier than setting up Pi-Hole itself, and given the added benefits, it is hard to argue against using Unbound. Here are my results.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 7: Proxmox or VirtualBox?

📅 August 18, 2022
“Which runs better on the Quieter2Q Mini PC: Proxmox or VirtualBox?”

This little project of running Pi-Hole and LibreNMS inside their own virtual machines on the Quieter2Q mini PC has been fun and interesting. Often, what looks good on paper does not always perform in the real world as expected despite best efforts, and this is one example.

After completely installing VirtualBox and Proxmox separately and using each VMM (Virtual Machine Monitor) individually for some time with the Quieter2Q, I have witnessed quirks and odd operation.

What is the best option: VirtualBox, Proxmox, or use the real hardware directly without any VMs?

Here are my conclusions after extended real-world usage of this dandy little project.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 6: Proxmox

📅 July 2, 2022
Proxmox is another virtualization environment based on Linux that allows you to create and manage virtual machines from within a web browser. It’s free, and it works great on the Mele Quieter2Q mini PC (Part 1).

In this article, we will replace VirtualBox with the free version of Proxmox 7.2 to see if we can achieve the same result of running Pi-Hole and LibreNMS in their own VMs.

Does it work? Yes, and the end result is the same as with VirtualBox. Proxmox simply provides another option. Here are my results.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 5: SNMP Install

📅 June 1, 2022
“How can I monitor more devices?”

With the biggie LibreNMS installation complete, we can now add devices to LibreNMS for monitoring. But can we add anything or must some conditions be met?

In order for LibreNMS to monitor a network device like a champ, the device must support SNMP. These devices run SNMP agents that communicate with LibreNMS, the SNMP server.

We have two devices we can add to our monitoring mix: the Quieter2Q host system itself and the VM running Pi-Hole. Right now, neither contains an SNMP agent, but we can fix that! This article will show how to install an SNMP agent in each Ubuntu Server and add it to LibreNMS. Then, we will add a non-SNMP device in order to check its availability.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 4: LibreNMS VM

📅 May 31, 2022
“Hey, router! Watcha doin’?”

A network monitoring system (NMS) allows us to monitor the performance and status of networking hardware, such as managed switches, routers, and servers. It operates using its own, dedicated protocol called SNMP (Simple Network Management Protocol) configured in a server-client arrangement where the NMS software (the server) polls SNMP agents (the clients).

The SNMP agents, when polled, return information about themselves that is then converted into pretty, multi-colored graphs by the NMS so we can answer basic questions about the network and its users. Questions such as,

“Which Ethernet port has the most activity?”

“What is the CPU temperature of the file server?”

“Has the fan failed in the router?”

“Why does Little Suzi’s computer show two hour’s worth of outgoing streaming activity at 1:00 AM every Saturday?”

…and much, much more.

A great piece of free software to achieve this is called LibreNMS, and we will install this in its own VirtualBox virtual machine (VM) running on the Quieter2Q.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 3: Pi-Hole VM

📅 May 30, 2022
With Ubuntu Server 22.04 set up and running as our host operating system, we are now ready to install VirtualBox and create our first virtual machine (VM) running Pi-Hole in its own Ubuntu Server 22.04 environment.

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 2: Ubuntu Server

📅 May 29, 2022
Following the description of the Quieter2Q mini PC hardware in Part 1, it is time to install an operating system.

We will install Ubuntu Server 22.04 since it lacks any extra software that normally installs during a typical GUI-based Linux distribution. For example, we will have no need for LibreOffice, so there is no need to install it. We can save storage space.

The main purpose of the mini PC is to run VirtualBox so we can run Pi-Hole and LibreNMS each inside its own virtual machine (VM). Therefore, we want to keep overhead to a minimum. This means no GUI. The mini PC will run as a headless system anyway, so there is no need to connect a monitor, keyboard, or mouse except during the installation.

Ubuntu Server requires a little more know-how than a GUI distribution, so this article will walk you through the steps needed to do this.

Ready to learn? Let’s have fun!

Pi-Hole and LibreNMS Virtual Fun on the Quieter2Q Mini PC – Part 1: The Hardware

📅 May 28, 2022
“A mini pc is great, but how does it perform as a network device hosting Pi-Hole and LibreNMS virtual machines?”

The Intel NUC project has proven to be a friendly genie that can grant almost any wish one might have on a private LAN. “SSH, FTP, DLNA, DNS, NFS — your wish is my command.” Just install it, forget it, go, and let the NUC run and run and run with practically no problems whatsoever.

This kind of reliability encourages bloat. After all, why not install Cockpit, VirtualBox, and an Apache2 repository server as well? Over time, the number of servers installed on a single device like this becomes tricky to manage and can eventually conflict. For example, Pi-Hole wants Lighttpd and LibreNMS wants Apache2 or nginx.

Surely, there must be an easier way to manage all of this, and indeed there is! The answer? Use a second mini PC to handle other services, such as Pi-Hole and LibreNMS, and then let each server run inside its own virtual machine using VirtualBox from the command line.

In this series of articles, we will look into a nifty little piece of computing joy, called the MeLE Quieter2Q, on which we will install Ubuntu Server 22.04, and run Pi-Hole and LibreNMS each inside its own dedicated virtual machine using VirtualBox that we will install and control completely from the command line. No GUI involved in order to save overhead.

Does it work, and if so, how well? In this part, we will look at the Quieter2Q hardware and compare storage benchmarks between eMMC and NVMe.