Sheridan Computers

27/03/2026

Remote support tools are a constant fight! Security, operating system compatibility with viewers, other stupid issues like fighting anti-virus software, using free tools to install paid tools. Finally, almost two years in to development, things are starting to look real - a proper browser based remote access tool.

A proof-of-concept of a remote access platform I’ve been building.The host/agent is installed on the target machine, but there is no client or viewer require...

05/02/2026

We’ve been working on a small open-source tool called isc2kea, built to help migrate OPNsense firewalls from ISC DHCP to Kea or dnsmasq.

OPNsense has deprecated ISC DHCP in favour of Kea, and while ISC still works as a plugin, migrating cleanly isn’t trivial — especially once you have more than one firewall. Doing it manually, one box at a time, is a pain in the ass.

isc2kea started out only migrating static mappings. Once we tried using it on real systems, it quickly grew into a full DHCP migration workflow:

🔹 migrates static mappings, subnets, and DHCP options

🔹 generates a clean updated config

🔹 safely switches from ISC DHCP to Kea or dnsmasq

🔹 restarts services in the correct order

includes verification so you can see exactly what would change before applying it

We’ve used it to migrate multiple firewalls end-to-end, and it’s designed to be repeatable and boring — the good kind of boring.

Important note: ISC DHCP hasn’t disappeared. It’s now an OPNsense plugin and still works. This tool isn’t about forcing migration — it’s about making it easier when you decide to do it.

isc2kea is open source, and we’d love more testing and feedback from anyone running OPNsense, especially with real-world configs.

Contribute to sheridans/isc2kea development by creating an account on GitHub.

31/01/2026

I went live expecting to be on my own, upgrading a firewall (OPNsense to latest 26.1 version) on a demo system and talking to myself 😅

Instead, around 50 people dropped by, the chat was great… and then Franco, the lead OPNsense developer joined the stream.

No edits, real-world behaviour, and we even uncovered a small UI bug along the way.
If you’re planning to upgrade to 26.1, this should give you a good idea of what to expect.

https://youtube.com/live/bFyAZqyRYc8?list=PLSJyoFloAkDo52MujFRHx1J1nZonLZtZE&si=CvJ6Ld-BPzmOJ4uh

This stream shows what people can realistically expect when upgrading to 26.1 — no edits, no scripting.Not a tutorial. This is about observing the upgrade pr...

29/01/2026

OPNsense 26.1 has been released and includes several important platform changes, including updates to firewall and NAT rule handling, intrusion prevention, IPv6 behaviour and DHCP defaults.

While existing configurations should continue to function, administrators should review key services after upgrading, particularly in production environments.

We’ve published a short overview of what changed and what to check before upgrading below.

Full blog post & video:

OPNsense 26.1 "Witty Woodpecker" released - what changed and what to check before upgrading

23/01/2026

We’ve published a new technical guide on setting up PPPoE on modern versions of OPNsense, including the new Point-to-Point device method introduced in recent releases.

The guide covers:
• Using the setup wizard for quick home or small office setups
• Manual configuration to understand how PPPoE is actually built
• Advanced scenarios where ISPs require VLAN tagging (for example VLAN 101)

👉 Full step-by-step guide here:
https://sheridancomputers.com/blog/view/videos/how-to-set-up-pppoe-on-opnsense-wizard-manual-setup-and-vlan

21/01/2026

Want OPNsense to block known malicious traffic automatically?

In this short walkthrough, we show how to integrate Q-Feeds with OPNsense to add curated threat intelligence without relying on massive, noisy blocklists.

This setup helps:
✅ Block outbound connections from compromised devices
✅ Reduce false positives
✅ Add another security layer with minimal overhead

Full guide and video here:
https://sheridancomputers.com/blog/view/videos/boost-opnsense-firewall-security-with-q-feeds-threat-intelligence

17/01/2026

For those that prefer a write-up regarding the latest opnsense update.

OPNsense 25.7.11 has been released, and at first glance it appears to be a routine patch update. However, several important changes in this version, along with what it prepares for in the upcoming 26.1 release, make this an update that network administrators and IT teams should not ignore.

OPNsense 25.7.11: Why This “Minor” Update Matters More Than It Looks

16/01/2026

🚨 OPNsense users: important changes are coming in version 26.1.

While OPNsense 25.7.11 looks like a small update, it’s actually preparing the way for major changes to how DHCP is handled, along with new host discovery, IPv6 fixes, and security updates.

We’ve published a short breakdown of what changed and what you should be testing before upgrading.

▶️ Watch the full video here: https://youtu.be/Iy6JplKRjH4

15/01/2026

New video showing how I install and secure FreeBSD on a Hetzner cloud server.

Since Hetzner doesn’t provide a FreeBSD image, the video starts with a manual install and then focuses on locking down the base system using PF and key-based SSH access.

The aim is a clean, secure baseline before anything else is added.

Fill Video:
https://youtu.be/I_yVW1h5jgw

26/12/2025

If your business needs IT support over the festive period, and as Captain James T. Kirk once asked, "I assume the situation is grim, and the odds are against us?"

Not all, we're here as usual. No automated or out of office messages, a human will answer your call.

In fact, today (Boxing Day) we replaced this failed generic router with an official OPNsense unit for a client.

www.sheridan.co.uk | 0800 030 4523

25/12/2025

An extremely productive Christmas Day 🎄

As IT professionals, one of the more uncomfortable situations is having EOL infrastructure terminating client traffic, especially when it’s managed by a third party and outside your patching or change control.

Took the opportunity to retire an end-of-life [managed] Cisco router on a leased line and replace it with OPNsense, an open source solution from Deciso, bringing the edge back under full visibility and control.

Result:
• Same IPv4 behaviour preserved
• Properly implemented native IPv6 (WAN /127 + routed /56)
• Transparent firewalling and routing
• Known update cadence
• Clear ownership of security posture

“Managed” doesn’t always mean “maintained”, and edge infrastructure is too critical to leave as a black box.

Although charges still apply for the manage service until the end of the contract, when it can be renewed as "wires only", this is a win in every way.

A good reminder that lifecycle management is as much about risk reduction as it is about features.

23/12/2025

New video is live: a hands-on look at the Minisforum MS-01.

After real-world use, it’s clear this isn’t an all-in-one mini PC. Not a great NAS, not an efficient router, and not really a desktop replacement.

It does however make sense as a compact Proxmox or XCP-NG virtualisation node with external storage.

The Minisforum MS-01 gets a lot of attention in the homelab space, but before you buy one, there are important things you should know. I walk through where t...