Microsoft Remote Desktop connection – ‘An internal error has occurred’ and ‘The server security layer detected an error (0x80090304)’ event ID 139.

An interesting issue that was discovered after deploying security certificates for Remote Desktop Authentication into the TPM of desktop computers and some (physical) servers, after go live with the security certificate clients could no longer connect with the error below being displayed in the Remote Desktop Services log on the server. The server security layer detected an error (0x80090304) in… Read more



ESPHome and the Waveshare E-Paper ESP32 & ESP8266 Driver Board

Having recently setup a Home Assistant server (in getting ready to move home) I’ve been playing with ESPHome as a way to easily integrate my projects into the home. With a view to make life a little easier for the next person I’ve included some sample config below which can be used with the Waveshare E-Paper ESP32 and ESP8266 Driver… Read more



Using a Raspberry Pi (or any Linux PC) as a Serial Console Server

A handy trick I learnt recently from this video (ICX Serial Console Server with Raspberry Pi by Terry Henry) which I’ve condensed into this screenshot guide. In short the ‘screen’ command in Linux can be used to turn any device into a serial console server – very handy if you need ‘out of band’ access to the management console of… Read more



PAN-OS and Connections Per Second in PRTG

If you are looking to build out Zone Protection Profiles on your Palo Alto Networks Next Generation Firewall then it can be handy to know just what your connections per second metrics look over time for each zone. Quite lucky Palo Alto Networks have a little (although not entirely descript) guide on where you can get this data – https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-admin/zone-protection-and-dos-protection/zone-defense/take-baseline-cps-measurements-for-setting-flood-thresholds/how-to-measure-cps.html…. Read more



Brief guide to (common-ish) HPE Aruba Fibre Optics

Not meant as a complete in depth guide but certainly enough to point you in the right direction here’s my list of the most commonly seen (from my point of view) HPE Aruba (e.g. the 2540, 2930F, 5400R series) fibre optics and their respective part numbers: The format is effectively <Speed> <Fibre Type> <Maximum Range> – <Part Code> 1Gbit Multi… Read more



MCP1700, wrong voltage without capacitors

In looking to keep occupied with the current pandemic going on I’ve taken my Microelectronics projects to a new level and have over the past few weeks kicked out a series of soil moisture sensors which are powered by battery (18650) with a small solar panel keeping them topped up. As the battery charges/discharges the voltage changes and moves outside… Read more



Extracting TRAFFIC, THREAT, CONFIG and SYSTEM syslog from a Palo Alto Networks Next Generation Firewall with Graylog

Graylog is a brilliant (and Open Source) tool to easily capture logs from a variety of systems including good old fashioned syslog. In the screenshot guide below you will learn how to use a set of extractors I constructed to parse out useful information from PAN NGFW syslog. The link to the source files mentioned is: https://github.com/jamesfed/PANOSGraylogExtractor



Backing up a Palo Alto Networks Next Generation Firewall with PowerShell

For some time there have been plenty of examples of backing up Palo Alto Firewalls with curl commands (extracting the files using the XML API) however that may not sit well with some Windows administrators who want to use PowerShell. As such I’ve put together the BackupPANNGFWConfig repo on GitHub which contains the scripts to get ahold of the API… Read more



The BUBM Cable Bag (and what I keep in it)

A bit of an odd post but given this bag is proving so very handy I thought it worth it! Having started a new job at the beginning of the year it was evident that I would need to carry around a bit more kit with me than previously, with Christmas just around the corner it was the perfect time… Read more