https://davidchristiansen.com Shipping software, securing systems, and figuring it out along the way en-gb Fri, 27 Mar 2026 18:36:38 GMT https://davidchristiansen.com/blog/multiplatform-docker-buildx-synology-nas https://davidchristiansen.com/blog/multiplatform-docker-buildx-synology-nas Fri, 27 Mar 2026 00:00:00 GMT Building multi-arch Docker images from an M1 Mac for an x86 Synology NAS hits a Docker API version mismatch you can't fix from either end. The workaround is running BuildKit as a standalone container on the NAS and connecting to it as a remote buildx driver. DevOps https://davidchristiansen.com/blog/openclaw-docker-hardened-homelab https://davidchristiansen.com/blog/openclaw-docker-hardened-homelab Fri, 27 Mar 2026 00:00:00 GMT OpenClaw is upfront about its security model: it's a personal agent that trusts its operator, and it tells you to harden it before exposing it. This post implements those recommendations as a Portainer stack on a Synology NAS, adding a Squid egress proxy to whitelist outbound domains, Docker secrets for credential isolation, and a read-only root filesystem. DevOps https://davidchristiansen.com/blog/run-hyper-v-docker-on-virtual-machine https://davidchristiansen.com/blog/run-hyper-v-docker-on-virtual-machine Thu, 17 Nov 2016 00:00:00 GMT TL:DR; On the Hyper-V host run Set-VMProcessor -VMName "<Your Virtual Machine Name>" -ExposeVirtualizationExtensions $true If you are like me, you may run all your Dev Environments from within Virtual... DevOps https://davidchristiansen.com/blog/howto-create-self-signed-certificates-with-powershell https://davidchristiansen.com/blog/howto-create-self-signed-certificates-with-powershell Thu, 08 Sep 2016 00:00:00 GMT This is a short post about how to create Self-Signed certificates with the New-SelfSignedCertificate  PowerShell module.  More specifically, this post will cover creating your own Root Certificate, ex... Security & Identity https://davidchristiansen.com/blog/solved-identity-server-v3-invalid-provider-type-cngkey-private-key-errors https://davidchristiansen.com/blog/solved-identity-server-v3-invalid-provider-type-cngkey-private-key-errors Wed, 11 May 2016 00:00:00 GMT In the scenario described in this post, you have encountered an error in your log that says the following: > Signing certificate has not private key or private key is not accessible. Make sure the acc... Security & Identity https://davidchristiansen.com/blog/fix-blurred-text-in-office-2016-skype-for-business-2016 https://davidchristiansen.com/blog/fix-blurred-text-in-office-2016-skype-for-business-2016 Mon, 07 Dec 2015 00:00:00 GMT Just a heads up.  If after you install Office 2016 you discover that the Skype For Business UI displays with horrendous burred font and scaling issues, then I may have a fix for you. The fix is rather... Development https://davidchristiansen.com/blog/clear-nuget-cache-on-build-server https://davidchristiansen.com/blog/clear-nuget-cache-on-build-server Fri, 29 May 2015 00:00:00 GMT Do you need to clear the Nuget cache on a build server which runs as a windows service? Simply navigate to the nuget cache store which is located in the temp directory for the system service accounts.... DevOps https://davidchristiansen.com/blog/self-signed-certificates-windows-apps-development https://davidchristiansen.com/blog/self-signed-certificates-windows-apps-development Tue, 16 Dec 2014 00:00:00 GMT > TL;DR; My solution was to save my self signed certificate in DER format, sticking it on a local IIS site, loading the URL to the certificate in my mobile emulator, opening the file (when prompted) a... Security & Identity https://davidchristiansen.com/blog/howto-auto-synchronise-files-upon-network-connection https://davidchristiansen.com/blog/howto-auto-synchronise-files-upon-network-connection Mon, 18 Aug 2014 00:00:00 GMT There are times where we need to work away from the office network and the safety of backup infrastructure.  What would be nice is to automatically synchronise files on my laptop whenever I connect to... DevOps https://davidchristiansen.com/blog/edit-github-wiki-with-images https://davidchristiansen.com/blog/edit-github-wiki-with-images Thu, 12 Dec 2013 00:00:00 GMT This post sets out to describe how to edit a GitHub wiki on your computer as an alternative to editing directly within the GitHub web UI. Cloning the GitHub Wiki to your computer The wiki content is... DevOps https://davidchristiansen.com/blog/glimpse-for-dotnetopenauth-1-3 https://davidchristiansen.com/blog/glimpse-for-dotnetopenauth-1-3 Thu, 18 Apr 2013 00:00:00 GMT Finally I got a chance tonight to update my DotNetOpenAuth extension for Glimpse. I've pushed the update out to Nuget so go ahead and update now. Install-Package DCCreative.DNOA4Glimpse   What does it... Security & Identity https://davidchristiansen.com/blog/how-simple-is-a-openid-connect-basic-client-c https://davidchristiansen.com/blog/how-simple-is-a-openid-connect-basic-client-c Mon, 16 Jul 2012 00:00:00 GMT John Bradley has just posted a great entry demonstrating how simple life is going to be for a Relying Party when it comes to OpenID Connect. I highly recommend you go and read it. > OpenID Connect pro... Security & Identity https://davidchristiansen.com/blog/solved-chrome-v18-self-signed-certs-and-signed-using-a-weak-signature-algorithm https://davidchristiansen.com/blog/solved-chrome-v18-self-signed-certs-and-signed-using-a-weak-signature-algorithm Mon, 02 Apr 2012 00:00:00 GMT So chrome has just updated itself automatically and you are now running v18 – great. Or is it… If like me, you are someone that are running sites using a self-signed SSL Certificate (i.e. when running... Security & Identity https://davidchristiansen.com/blog/dotnetopenauth-debugging-and-tracing-openid-and-oauth-on-asp-net-or-mvc-using-glimpse https://davidchristiansen.com/blog/dotnetopenauth-debugging-and-tracing-openid-and-oauth-on-asp-net-or-mvc-using-glimpse Mon, 11 Jul 2011 00:00:00 GMT Synopsis: Understanding exactly what is happening under the hood when it comes to working with OpenID and OAuth can be challenging even for the seasoned IDM developer. What I have found to help, is be... Security & Identity https://davidchristiansen.com/blog/logparsergraphing-ping-results https://davidchristiansen.com/blog/logparsergraphing-ping-results Tue, 25 Jan 2011 00:00:00 GMT Here is a nifty little example of how to pipe console output to Microsoft LogParser, in this case the results of a ping against Google. ping -n 15 www.google.co.uk | "%pathTologparser%\\LogParser" "SE... Cloud & Infrastructure https://davidchristiansen.com/blog/fix-nhibernatelog4net-in-windows-service-filenotfoundexception https://davidchristiansen.com/blog/fix-nhibernatelog4net-in-windows-service-filenotfoundexception Thu, 20 Jan 2011 00:00:00 GMT When using nHibernate in a windows service you may find that you encounter FileNotFoundExceptions when trying to load assemblies or external configuration files. Typically this is in scenarios where y... Development https://davidchristiansen.com/blog/howto-creating-a-dummymock-webservice-asmx-from-a-wsdl-file https://davidchristiansen.com/blog/howto-creating-a-dummymock-webservice-asmx-from-a-wsdl-file Mon, 29 Nov 2010 00:00:00 GMT Sometimes it is helpful to mock a xml webservice for the purpose of testing against it without invoking the actual service. There are several reasons why this can be a good idea, such as when the serv... Development https://davidchristiansen.com/blog/solved-id6035-cannot-create-a-hashalgorithm-object-identifier-oid-is-unknown https://davidchristiansen.com/blog/solved-id6035-cannot-create-a-hashalgorithm-object-identifier-oid-is-unknown Mon, 29 Nov 2010 00:00:00 GMT Implementing the Windows Identity Foundation of Windows Server 2003 and experiencing errors such as the following? Exception: System.NotSupportedException, mscorlib, Version=2.0.0.0, Culture=neutral... Security & Identity https://davidchristiansen.com/blog/howto-using-dotnetopenauth-v3-4-x-with-asp-net-mvc2 https://davidchristiansen.com/blog/howto-using-dotnetopenauth-v3-4-x-with-asp-net-mvc2 Fri, 16 Apr 2010 00:00:00 GMT When targeting ASP.NET MVC 2, this assemblyBinding makes MVC 1 references relink to MVC 2 so libraries such as DotNetOpenAuth that compile against MVC 1 will work with it. Security & Identity https://davidchristiansen.com/blog/wildcard-certificate-mapping-multiple-web-servers-using-single-ip-address https://davidchristiansen.com/blog/wildcard-certificate-mapping-multiple-web-servers-using-single-ip-address Mon, 01 Jun 2009 00:00:00 GMT Prerequisites ------------- MakeCert.exe (Which should be part of a visual studio install or downloadable here) winhttpcertcfg.exe (downloadable here) APPCMD (Part of Vista / Server 2008 / Wi... Cloud & Infrastructure