Palo Alto NGFW, decryption and images in Slack not displaying or uploading

You may find that when doing decryption on a Palo Alto Networks Next Generation Firewall that images in Slack channels are not displayed or are only shown in a very low resolution – in addition images cannot be uploaded. When inspecting the HTTP error messages in your browser a 503 response may also be seen. To top off the issue… Read more



PRTG REST API, PowerShell and UTF8

An issue that I’ve now run into a few times now so I thought it was worth a blog post – if you are using the REST Custom sensor within PRTG Network Monitor you may see the error below if you have generated your REST configuration using PowerShell. XML: The returned XML does not match the expected schema. (code: PE233)… Read more



Processing Cortex XDR Syslog/CEF with Graylog

It’s a bit of an odd situation but sometimes you might want to take information from a cloud service in this case Cortex XDR from Palo Alto Networks and drag it into an on premise logging service. This guide will have a look at how to get this log data in as well as parse it such that you can… 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



Intune Certificate Connector and 0x80094800

In configuring the Microsoft Intune Certificate Connector and attempting to issue certificates to your client via Intune you might run into the error message below. IssuePfx – COMException: System.Runtime.InteropServices.COMException (0x80094800): The requested certificate template is not supported by this CA. (Exception from HRESULT: 0x80094800)at CERTENROLLLib.IX509CertificateRequestPkcs10V2.InitializeFromTemplateName (X509CertificateEnrollmentContext Context, String strTemplateName) at Microsoft.Management.Services.NdesConnector.MicrosoftCA.GetCertificate (PfxRequestDataStorage pfxRequestData, String& certificate, String& password) Failed to issue… Read more



PRTG, Graphs and the alternatives to just displaying the average

The default graph options in PRTG (Setup > System Administration > User Interface) for extended periods of time (e.g. over 10 days) will display the average over a set period (e.g. 1 hour) – while this may be ideal for some data on occasion you may want to display the maximum or minimum value for the data over that period…. 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



MBR2GPT: Disk layout validation failed for disk 0

So after realising that my desktop PC has been running in BIOS mode (how 1970s and probably the result of multiple clones from HDD to 10k HDD, to 10k HDD in RAID0 to SSD and to another SSD) and with a free weekend I thought it was time to have a look at the MBR2GPT tool. However in running the… Read more