Cracking the Code: Navigating Network Nightmares with Home Assistant, LibreNMS, and Wireshark

Introduction:

Hey there! Ever found yourself scratching your head over a quirky network issue that just won't quit? I recently had my fair share of head-scratching moments when network broadcast storms started causing serious disruptions in our switches and wireless access points. In this post, I'm breaking down the steps I took to unravel this persistent, network mystery.

Setting the Scene:

Picture this – network switches and access points dropping off the radar every few nights. To get to the bottom of it, I needed to gather some intel without losing sleep, especially as these problems seemed to occur in the middle of the night.  First move? Configuring Home Assistant to ping, with the Ping integration, a crucial switch and give me a notification on my phone when things go south. It became my silent night watchman, marking the time when the broadcast storm kicked in.

The Quest for Network Clarity:

LibreNMS, a network monitoring system, was my next stop. Although it did show spikes in network bandwidth, the specifics were elusive. SNMP logs lacked the juicy details needed for a deep investigation.

Enter rsyslogd:

To beef up my data game, I brought in rsyslogd on a Proxmox server. This Linux container was configured to capture logs from the admin VLAN, where switches and access points were. This did capture a lot of data, however, drowning in logs was not my idea of fun.  It was too hard to find the root cause of these issues.

Mastering Home Network Security: A Step-by-Step Guide to Fortify Your DNS with Pi-Hole and Raspberry Pi Across Multiple VLANs

Recently, I delved into the realm of setting up secure DNS for our home network, aiming to encrypt DNS requests en route to the name server. Unfortunately, Unifi lacks support for secure DNS (neither DoH nor DoT). To address this, I decided to explore the installation of Pi-hole on a Raspberry Pi at home.

However, the standard Pi-Hole install for Raspberry Pi required additional setup steps on my network. Firstly, Pi-hole lacks built-in support for secure DNS, necessitating an additional configuration. Secondly, the default Raspberry Pi lacked VLAN support, prompting me to configure it to function seamlessly within our network.

Raspberry Pi and Pi-hole Setup

I began by installing the Raspberry Pi OS Lite 64-bit on the Raspberry Pi, intending to use it as a headless device on the network. Once the operating system was installed and updated, I proceeded to install Pi-hole. This was a straightforward process, thanks to Pi-hole's automated installation script.

curl -sSL https://install.pi-hole.net | bash

Setting up DNS over HTTPS for Pi-hole

To ensure secure DNS, I followed the instructions on the Pi-hole site to configure cloudflared, allowing DNS requests to be made over HTTPS. Once configured, Pi-hole forwards requests to cloudflared, which handles DNS requests securely.

Enabling Support for Multiple VLANs

While Pi-hole successfully handled requests for the native network, extending its support to other VLANs posed a challenge. Instead of opting for solutions involving firewall rule modifications to permit VLAN requests to the native network, I chose to ensure the Raspberry Pi could seamlessly join the VLAN networks I intended to use Pi-hole on.

Following the instructions on this page for enabling VLAN support on the Raspberry Pi, I configured an interface for each VLAN I wanted the Pi-hole to respond on.

Silencing the Breeze: Upgrading Legion Network Racks for Whisper-Quiet Performance

In our home, we utilize a couple of Legion 18 network racks. These particular 18U network racks are designed to be compact, making them suitable for placement in closets or offices. Additionally, they come equipped with built-in cooling features, specifically two 120mm fans located at the top of the rack.

However, while the built-in cooling is a valuable feature, I couldn't help but notice that the noise generated by the fans can be quite noticeable, particularly in quieter environments. One of the main reasons for this is that the fan speed is fixed; there's only an on/off switch available. Consequently, you can either turn the fans off entirely or run them at their default, relatively loud speed. This limitation led me to seek out replacement fans for the rack.

Stock fans from the Legion 18 network rack

After conducting some research, I decided to opt for the AC Infinity Rack ROOF Fan Kit. This kit includes two 120mm fans that can be connected to a provided fan controller, which, in turn, connects to a power source. The fan controller offers precise control over the fan speed, allowing for quieter operation.