A few weeks ago, we run into a strange problem. We were in the middle of our Let’s Encrypt rollout, in which we create a dedicated certificate for each of our domains. Since we run multiple domains on a single web server with only one IP address, we need to activate SNI (Server Name Indication). That worked on all our servers - expect one. That server gave us this useless error page:
We started a few weeks ago to target .Net Standard in our class libraries. While our applications remain for the foreseeable future on the .Net (Full) Framework, we like to start moving code towards .Net Core. Building our solutions in Visual Studio worked without any problems, but as soon as we try to do that in Azure DevOps, we run into this error:
C:\Program Files\dotnet\sdk\2.2.105\Sdks\Microsoft.NET.Sdk\targets\Microsoft.PackageDependencyResolution.targets(208,5): Error NETSDK1004: Assets file 'c:\agent\_work\95\s\***\obj\project.assets.json' not found. Run a NuGet package restore to generate this file.
There is always that one machine that you cannot upgrade on a current version because some dependencies outside of your control demand that specific configuration. You may postpone the inevitable, but one day you run out of luck. If your box is a web server, that day will come sooner than you think.
Out of the box, IIS on Windows Server 2008 R2 offers Transport Layer Security only in version 1 (TLS 1.0). That version is outdated and should not be used for securing any HTTPS traffic. Unfortunately, you do not see the version your browser uses to connect to a web server and so it may be that this protocol is still active. If this is the case, your users will not be able to visit your web site when all major browsers block that version at the beginning of 2020.
Last week I run into this annoying problem when I tired to run the .Net samples for Docker:
Step 7/23 : RUN dotnet restore
—> Running in ce2d8740cf2e
Restore completed in 389.74 ms for C:\app\dotnetapp\dotnetapp.csproj.
Restore completed in 220.85 ms for C:\app\utils\utils.csproj.
C:\Program Files\dotnet\sdk\2.2.402\NuGet.targets(123,5): error : Unable to load the service index for source https://api.nuget.org/v3/index.json. [C:\app\dotnetapp.sln]
C:\Program Files\dotnet\sdk\2.2.402\NuGet.targets(123,5): error : No such host is known [C:\app\dotnetapp.sln]
The command ‘powershell -Command $ErrorActionPreference = ‘Stop’; $ProgressPreference = ‘SilentlyContinue’; dotnet restore’ returned a non-zero code: 1
Popular technologies come with an enormous amount of "promotional" material. Docker is no exception to this rule: you find an endless stream of things to read, to watch and to listen to about Docker and containers. With only a limited amount of time at your hand, where should you spend it?
A few weeks ago, I was facing the same problem. I found many things that were not so useful, and I spent far too much time on them. However, at the same time I found the 3 resources I like to share with you today. I hope they can be of great use for you too. I am still new to the topic and appreciate if you post your favourite books, videos and tutorials as a comment to this post.
Visual Studio 2019 offers some great help to use Docker with ASP.Net applications on the .Net full framework. The support for Docker improved over the last versions of Visual Studio and is now on a level where you nearly can't get it wrong. If all is working, you can start your application inside a Docker container with the click of a button:
Prerequisites: You need to install Docker Desktop and set the format of your containers to Windows. You can run .Net core applications on Linux, but the full framework needs Windows.
Over the last weeks I run in to constant login problems with my Git repositories hosted in Azure DevOps. One day everything works, the next day I cannot connect. I seems as if Microsoft is pushing more actively the move to personal access tokens and the older approach with alternate credentials comes to an end. Those tokens offer more flexibility and you can create them in just a few simple steps.
Let's Encrypt offers free SSL certificates to protect the traffic between your website and the visitors. They are as good as the expensive commercial ones, but they need to be renewed every three months - thanks to automation, this is not a problem.
I use Let’s Encrypt for all my sites and never had any problems. A few clicks on the management interface of Plesk and all the traffic went over HTTPS – and the renewal just worked out of the box. With that experience I thought that using Let’s Encrypt on Azure should be no challenge at all. How wrong I was.