Scott Hanselman

LLBLGen Pro for .NET and .NET Core - Database Entity Modeling with any ORM

June 12, '17 Comments [20] Posted in Data
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There's opinionated frameworks, and then there's opinionated frameworks that also respect your opinion. LLBLGen is one of those. For many years it's been a great entity modeling tool as well as an excellent ORM (Object Relational Mapper.) It also supports all major ORMs in the .NET space like Entity Framework, NHibernate, Linq to Sql as well as, of course, their own included LLBLGen Pro Runtime Framework. It works with VS2015 and VS2017 and is actively supported and extremely actively developed. It's because of that active development that I wanted to check it out. It's got Getting Started videos and a TON of docs, so I figured I could do some damage pretty quickly with a 30 day trial.

NOTE: Just a reminder, I don't do sponsored posts for software. I just felt like checking out LLBLGen because it's been a few years since I looked at it least. All my observations are my own, unfiltered, as I know you like them, Dear Reader.

You can do Database First - a technique that is crucial for so many of us with existing databases but often downplayed with other ORMs - as well as Model First and then generate classes.

I decided to start with one of the newer SQL Server 2016 sample databases called Worldwide Importers. There's localdb versions, Azure SQL Database versions, and SQL Server 2016 backups. I made a database in Azure, uploaded a "bacpac" file to Azure storage, and imported the database into SQL Azure. Although I certainly could have done the work locally, I can get more horsepower in the cloud.

When I make a new Project in the LLBLGen GUI I can pick from a ton of different ORMs including 5 (!) versions of Entity Framework including EFCore, as well as NHibernate 4v and Linq to SQL (which is a nice touch as I have two L2S projects still in production.)

LLBLGen supports a bunch of ORMs

The WorldWide Importers sample is a nice one as it's typical and non-trivial in complexity. I pointed LLBLGen at it and let it rip. Make sure you wait until your database is totally restored into SQL Azure or your SQL Server or you may get weird errors about Zombie Transactions.

LLBLGen chewing on the DB

When it's done, you'll get an Errors & Warnings pane that will tell you how many stored procs, tables, views, etc that were imported, and that they are "unmapped," which is cool since you haven't mapped them.

Smart Errors in LLBLGen

You can switch your Target ORM Framework after you've imported your Data Model, but you really should put a little thought into how your database is structured and whether or not your preferred ORM supports all the features you (may) have used heavily in your Database. For example, if you're a very "stored proc"-style shop, it would be a problem if you really wanted to use an ORM that didn't support stored procs.

LLBLGen is rather extraordinary in that it not only has smarts about what's possible and what's not, but it also offers you a multiple-choice solution framework when something is wrong. For example, there's a mapping here that isn't support, so it's offering me three options to fix it, including (of course) changing the offending entity by changing/adding fields.

LLBLGen offers multiple fixes and can do them right there in the Errors pane

Once you have a valid model and have corrected any issues and/or made appropriate changes, you can Generate Source Code for your target platform, language, and ORM Framework.

Generating Code with LLBLGen

Make no mistake about it - there's a LOT of depth here. There's multiple kinds of templates and tons of options. You may not get it all right on the first try, but it's very forgiving. Just remember where the authoritative source of truth is. Is your model the truth? Or your database? As you move forward (depending on where you started) your source of truth will likely change. You can use any of the many code generators or expand them with your own modifications and metadata.

You'll also likely get addicted to the nice visual editors for entities (a good thing!).

LLBLGen Visual Editors

Quick Model is also nice if you want to visualize (and change) relationships between just a few of your many tables.

LLBLGen Visual Designer

If you get fast enough, with practice you can use the Quick Model editor and it's Command Input palette to model most of a new database when interviewing domain experts. The visual designer is fast and flexible.

I've truly barely scratched the surface of this deep tool. The pricing is very reasonable considering all it does.

Have you used LLBLGen or similar tools lately? What's been your impression?

Sponsor: Big thanks to Raygun! Don't rely on your users to report the problems they experience. Automatically detect, diagnose and understand the root cause of errors, crashes and performance issues in your web and mobile apps. Learn more.

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Trying .NET Core on Linux with just a tarball (without apt-get)

June 8, '17 Comments [14] Posted in DotNetCore | Linux
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There's a great post on the .NET Blog about the crazy Performance Improvements in .NET Core that ended up on Hacker News. The top comment on HN is a great one that points out that the  website could be simpler, that it could be a one-pager with a clearer Getting Started experience.

They also said this:

Also, have a simple downloadable .tar.gz which expands into /bin + /lib + /examples. I loved C# back in my Windows days and I moved to Linux to escape Microsoft complexities and over-reliance on complex IDEs and tools, scattered like shrapnel all over my c:/

I will not run apt-get against your repo without knowing ahead of time what I'm getting and where will it all go, so let me play with the tarball first.

This is a great point, and we're going to look at revamping and simplifying the with this in mind in the next few weeks. They're saying that the Linux instructions, like these instructions on installing .NET Core on Ubuntu for example, make you trust a 3rd party apt repro and apt-get .NET, while they want a more non-committal option. This gets to the larger "the website is getting bigger than it needs to be and confusing" point.

.NET Core from a tarbar on Linux

Trying out .NET Core from a tarball

Go to and download the .tar.gz for your distro to a nice local area.

NOTE: You MAY need to apt-get install libunwind8 if you get an error like "Failed to load /home/ubuntu/teste-dotnet-rc2/, error: cannot open shared object file: No such file or directory" but libunwind isn't very controversial.

Once you've unziped/tar'd it into a local folder, just be sure to run dotnet from that folder.

Desktop $ mkdir dotnetlinux
Desktop $ cd dotnetlinux/
dotnetlinux $ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.2 LTS
Release: 16.04
Codename: xenial
dotnetlinux $ curl -o dotnet.tar.gz
dotnetlinux $ tar -xvf dotnet.tar.gz
dotnetlinux $ cd /mnt/c/Users/scott/Desktop/localdotnettest/
localdotnettest $ ../dotnetlinux/dotnet new console
Content generation time: 103.842 ms
The template "Console Application" created successfully.
localdotnettest $ ../dotnetlinux/dotnet restore
Restoring packages for /mnt/c/Users/scott/Desktop/localdotnettest/localdotnettest.csproj...
localdotnettest $ ../dotnetlinux/dotnet run
Hello World!

There aren't samples in this tar file (yet) but there are (some weak) samples at you can clone and run them from samples. Note from the ReadMe that is the jumping off point for the other repos.

The more interesting "samples" are the templates you have available to you from "dotnet new."

localdotnettest $ /mnt/c/Users/scott/Desktop/dotnetlinux/dotnet new

Templates Short Name Language Tags
Console Application console [C#], F# Common/Console
Class library classlib [C#], F# Common/Library
Unit Test Project mstest [C#], F# Test/MSTest
xUnit Test Project xunit [C#], F# Test/xUnit
ASP.NET Core Empty web [C#] Web/Empty
ASP.NET Core Web App mvc [C#], F# Web/MVC
ASP.NET Core Web API webapi [C#] Web/WebAPI
Solution File sln Solution

dotnet new mvc --auth None --framework netcoreapp1.1
dotnet new classlib
dotnet new --help

From here you can "dotnet new web" or "dotnet new console" using your local dotnet before you decide to commit to installing .NET Core from an apt repo or yum or whatever.

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About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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RetroPie and X-Arcade Tankstick - The perfect Retro Arcade (plus keybindings and config and how-to)

June 7, '17 Comments [5] Posted in Gaming
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Eight years ago I stumbled on the husk of an old arcade cabinet and along with my buddy John Batdorf, proceeded to reclaim the cabinet, refinish, paint, and turn it into a proper MAME (Multi-Arcade Machine Emulator)

As an aside, a bit after helping me this project, John happened to start an amazing business making furniture with reclaimed wood, check him out at Amazing stuff, truly.


Last week I build a RetroPie into an X-arcade tankstick. This is my best retro arcade yet because it's got HDMI out and I can take it to friends' houses. That said, I'm going to briefly go over my other systems because they may be more attractive for your needs. If you have no patience, scroll down.

A full size MAME Cabinet - The Complete MAME Cabinet How-To

I wrote up a complete 7 part series on making your own MAME Arcade Cabinet. It's super fun and will only take a few weekends and perhaps a few hundred bucks.

  1. Cabinet and Power
  2. Monitor and Mounting
  3. Control Panel
  4. Sound and Lights
  5. Paint and Art
  6. Computer Hardware and Software
  7. Success and Conclusion

When I made my first MAME cabinet I put a small "Shuttle PC" inside. The MAME system is in my office and runs to this day on Windows 7 with a HyperSpin frontend.

Software Disclaimer 1: There's all sorts of iffy legal issues around emulating arcade games with boards/ROMs you don't own. This series of posts has nothing to do with that. I do own some original arcade boards, but if you want to emulate arcade games with MAME (Multiple Arcade Machine Emulator), you can search the 'tubes. What I'm doing here is putting a computer in a pretty box.

Hardware Disclaimer 2: Many folks that build arcade cabinets have a purist view of how these things should be done. They will prefer original Arcade CRT monitors and more expensive, higher quality parts. I am more of a pragmatist. I also have no idea what I'm doing, so I've also got ignorance on my side.

There's been a huge amount of work done in the last few years to reconcile the dozens of emulators and systems and the nightmare of keybindings, menus, and configuration. My first MAME machine was a few hours to install and literally weeks of messing around with the settings of various emulators. I started with the legendary v1 "X-Arcade Tankstick" that had was effectively a PS2 keyboard. I took it apart and built it into my MAME system's control panel. I then needed to tell each individual emulator the key codes for up, down, left, right, a, b, x, y, etc. Each emulator had a different configuration file. Some were INI files, some XML, some freaking magic.

It's a lot to ask in 2017 to dedicate a complete PC to a retroarcade - in fact, it's just not necessary. A $35 Raspberry Pi 3 (or even an overclocked Raspberry Pi 2) has enough power to handle all but the most complex emulators.

Tiny Raspberry Pi Powered "CupCade"

Later I discovered RetroPie and built a tiny "cupcade" with plans from AdaFruit.  It is/was a tiny little thing that with just a basic menuing system but it got me thinking about how powerful the Raspberry Pi is. The AdaFruit site has all the plans and parts you can buy. I had a local makerspace laser-cut the case. Assembly was just a weekend.

AdaFruit's CupCade

Hyperkin - An off-the shelf RetroArcade Console

We also picked up a Hyperkin Retron console. This is a great legal way to plan retro games because it requires actual cartridges. We buy our games at Retro Game Trader. If you are EVER near Portland you HAVE to stop and check it out. It's insane.

There's a old joke about building a retro arcade machines - Is it more fun to play retro arcade games, or is it more fun to build a retro arcade machine with a cool front-end where every keybinding works in every emulator but you never get around to playing games?

A RetroPie inside an X-Arcade Tankstick

There's a whole series of gotchas that took me a few weeks to work through when taking a Raspberry Pi, RetroPie software, and an X-Arcade and getting them to work well together.

THIS blog post is going to be a collection of all the stuff I wish I'd known BEFORE I started on this path. Even one of these tips would have saved me an hour, so the collection of them is days of googling, forum reading, and trial and error.

Start with this 7-part short video series (they are less than 10 min long, so it's not so scary) on the X-Arcade with the RetroPie.

Parts List

You'll want at least these things to start.

  • Raspberry Pi 3 - Don't skimp, get a 3. Yes you can use a 2, but you'll be far happier with a 3.
  • Raspberry Pi 3 Heatsink Set - Raspberry Pi's can be persnickety. Spend the $5 and get a heatsink.
  •  128gig high-speed microSDXC card - Get the largest and fastest microSD card you can get. Class 10 is ideal.
  • 2amp+ powersupply with a 5 foot microUSB cable. Make sure your powersupply does at LEAST 2 amps. Less and your Raspberry Pi may not boot up with keyboards or mice attached.
    • Remember that the goal here is to be able to plug this into your TV while you're sitting near or on your couch. You might even want a longer cable.
    • Make sure the microUSB powersupply cable length matches your HMDI cable length. You're only as useful as the shortest cable between these two.
  • PS2 keyboard - Yes, PS2. I picked one up at Goodwill or a local Thrift Shop. You'll need this to program the X-Arcade Tankstick. You change its mode switch, press a button on the controller while simultaneously pressing a key on the PS2 keyboard. You'll repeat this until all your keys are set.
  • Also, you can never have too many cable ties.

And finally, last but not least. An X-Arcade Stick. You can get them with or without a Trackball (which acts as an independent mouse and uses its own additional USB cable). As I mentioned, I'd long-been a fan of all X-Arcade products. Their stuff is legendarily reliable and built like, well, a tank. They're fantastic in that you can even get adapters for your X-Box, X-Box One, Wii, Dreamcast, whatever.

My brother recently found an X-Arcade stick at a local thrift story for $30 and grabbed it for me. I opened it up and noticed it was the PS2 version from years ago. Fear not - you should be aware that there is the PS2 X-Arcade that requires a PS2 keyboard be attached, and there's the newer USB version.  Here's the epic part - and reason #564 why I love X-Gaming as a company - you can upgrade the electronics in your v1 X-Arcade stick with a simple board for $35. And I did just this. This kit takes any existing X-Arcade to the latest hardware and you're going to want the latest if you want your X-Arcade to work smoothly with RetroPie.

I took the back off the X-Arcade and threaded the HDMI cable and USB micro cable through the back holes. I 3D-printed a case (the yellow cage in the photo below) for the Raspberry Pi but really any case will do as long as wires aren't touching wires. There's an RS232 cable and the vestigial green PS2 male that you can tuck away in there. I used the remaining hole to keep the purple PS2 female connector handy as it'll be used for "programming" the keys for the X-Arcade.

Hey it's a Raspberry Pi 3 shoved into an X-Arcade. That's not very sophisitcated.

Yes, it's janky, but all I had was electrical tape. Ideally I'd get a rubber gasket for the wires to keep the tension off the Raspberry Pi and make it more "kid safe."

Photo Jun 06, 11 46 29 PM

Again, follow these videos. If you're a little technical it's pretty straightforward stuff. The general idea is this.

  • The Raspberry Pi uses the SD Card as its hard drive.
  • The X-Arcade is a keyboard and you'll have the PS2 keyboard temporarily plugged into it for setup.
  • The Raspberry Pi 3 is best not only because it's fast but it's also got built-in WiFi. If you use a Raspberry Pi 2, you'll need a Wifi adapter.
  • With your computer, you will use Win32DiskImager to copy a pre-made image of RetroPie to the SD Card.
  • You'll put the SD Card into the Pi, connect the X-Arcade via USB to the Pi, connect the PS2 keyboard to the X-Arcade , connect the Pi's HDMI to a monitor or TV, connect the power, and boot up.
  • You'll follow some on-screen prompts (again, see the videos) and setup RetroPi.
  • You'll program the X-Arcade to act as a keyboard.
  • Then you'll see what works and start debugging.
    • Debugging often consists of using putty and/or Bash for Windows to ssh into the Raspberry Pi. The user name is pi and the password is raspberry so that's usually "ssh pi@retropie" then the password.

Little Gotchas when Hooking up RetroPie and an X-Arcade

Now to the little details that took me weeks that will hopefully help you.

  • Xarcade2Jstick vs standard keyboard mapping - Some people swear that the X-Arcade stick will/can get detected as a joystick using a user-space driver called Xarcade2Jstick. This driver is built into Retropie now and it takes your keyboard/xarcade and "lies" to the system and makes it look like two gamepads. Some folks swear by it. I fought with it for a week and decided that since I understand keyboards, I would just stick with keyboard mapping. Your mileage may vary, but the good thing to know (and try) is that if your system "just works" when you boot up, then perhaps Xarcade2jstick worked amazingly for you and you can skip a LOT of this mess. Sound off in the comments.
    The gent who made the videos also believes that keyboard mapping is more reliable and recommends this "non-standard" set up and programs it in "bank 2" of the X-Arcade. That means the toggle switch is in the second position inward, away from the serial point when you program it. He recommends this layout and I've used it also. This is a screenshot from his video.
    Keyboard mappings are in the linked to Zip file
  • NOTE: I needed to go into optional components in RetroPie setup and specifically disable xarcade2jstick. You can re-run RetroPie-setup from the command line as often as you like.
    cd RetroPie-Setup
    sudo ./
  • Keyboard Bindings for RetroArch compliant emulatiors - Now, I think I understand this, but if I get it wrong, let me know in the comments. There is an organization called "libRetro" that comprises the libRetro library, the RetroArch frontend that runs libRetro programms, and Lakka, a Linux that's meant for retroarcades. You don't need to sweat Lakka as you used a default RetroPie image. But RetroArch you'll be hearing a lot about. Remember earlier when I was complaining about all the trouble configuring emulators? RetroArch has scoped, nested config files (with includes) that allow you specify your config and keyboard/gamepad/joystick mapping once and then participating emulators will "just work." 
    Another way to look at it is this. In the past you needed lots of emulator programs from lots of people with lots of config that was all different. Retroarch tries to unify all of this so there's "cores" for each emulated system that Retorarch calls out to for the emulation.
    Follow the videos, but you'll basically go to /opt/retropie/configs/all and edit retroarch.cfg to support the keymapping above. MOST of the emulators will pick these settings up. But not all. More on that in a second.

    Like this:

    input_player1_a = t
    input_player1_b = r
    input_player1_y = q
    input_player1_x = w
    input_player1_start = num1
    input_player1_select = num5
    input_player1_l = e
    input_player1_r = y
    input_player1_left = left
    input_player1_right = right
    input_player1_up = up
    input_player1_down = down
    input_player1_l2 = u
    input_player1_r2 = i
    input_player1_l3 = nul
    input_player1_r3 = nul

    input_player2_a = j
    input_player2_b = h
    input_player2_y = d
    input_player2_x = f
    input_player2_start = num2
    input_player2_select = num6
    input_player2_l = g
    input_player2_r = k
    input_player2_left = a
    input_player2_right = s
    input_player2_up = o
    input_player2_down = p
    input_player2_l2 = l
    input_player2_r2 = z
    input_player2_l3 = nul
    input_player2_r3 = nul

  • Exiting Games with the Xarcade controller - One of the most common questions I saw in the forums was "I can move around in the menus and launch and emulator but I can't exit it!" Folks were forced to pull the plug and hard reboot which isn't a sustainable solution. The xarcade has a "flipper" (imagine a pinball flipper's controlling button position) button on each side. The standard hotkey for exiting an emulator has historically been pressing the Player 1 start button PLUS the left flipper button. That's the 1 and 5 keys together if you look at the diagram above.
    You'll want to go to /opt/retropie/configs/all and edit retroarch.cfg and confirm that you have these lines somewhere:
    input_enable_hotkey = num1
    input_exit_emulator = num5
    Then launch emulationstation (or reboot), launch an emulator, and press P1 and left bumper/flipper. You'll also come to know the left and right flipper buttons as the virtual "insert coin" buttons for Player 1 (P1) and Player 2 (P2) respectively.
  • Some emulators don't listen to RetroArch settings - Depending on the RetroPie image you downloaded, you may find that some emulators don't listen or respect your core retroarch.cfg settings. Or, perhaps the defaults buttons don't feel right. For example, Sega controller buttons are two rows of three buttons each. You can override your settings to make your xarcade more intuitive. Go to /opt/retropie/configs/megadrive and edit the retroarch.cfg in there. Note that it includes the MAIN "all" retroarch so you're just overriding some settings on an emulator by emulator basis.

    # Settings made here will only override settings in the global retroarch.cfg if placed above the #include line

    input_player1_a = y
    input_player1_b = t
    input_player1_y = r
    input_player1_x = w
    input_player1_l = q
    input_player1_r = e

    input_player2_a = k
    input_player2_b = j
    input_player2_y = h
    input_player2_x = f
    input_player2_l = d
    input_player2_r = g

    input_remapping_directory = /opt/retropie/configs/megadrive/

    #include "/opt/retropie/configs/all/retroarch.cfg"

  • MAME isn't working at all with the Xarcade - This hit me and I see lots of folks struggling. If the MAME core/emulator you're using doesn't integrate with RetroArch, you may need to manually keymap within MAME itself. Use the attached keyboard (while it's still attached) and when inside MAME press Tab. You'll go into the "Input (general) and go down the line one at a time and remap the keys. It's NOT obvious that you have to press and hold the buttons on your XArcade before MAME will pick up the new mapping. It's also not obvious that if you press AGAIN and hold that you can tell MAME another alternate key. In other words, the "OR" key. As in "1 OR 5" if you like.
    You might like to know that mame-advmame stores these configurations in /opt/retropie/configs/mame-advmame in *.rc files. For example, I had advmame-0.94.0.rc and wanted to be able to exit MAME from my xarcade. If I had a keyboard attached, I'd press "ESC" but with the Xarcade I wanted "Player 1 plus Left Flipper" to work. Then I wanted either "Enter" to confirm, or the main button for Player 1. I ended up with this. Again, this is for non-RetroArch advmame, but it makes the larger point in case you run into these kinds of emulators.

    input_map[ui_pause] keyboard[0,enter] or keyboard[0,tab] keyboard[0,up]
    input_map[ui_select] keyboard[0,enter] or keyboard[0,q]
    input_map[ui_cancel] keyboard[0,5] keyboard[0,1] or keyboard[0,esc]

That pretty much covers all the hairpullingout of the last few weeks. The result is very nice though. I hope you make one also!

Photo Jun 07, 12 58 22 AM

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About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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.NET and Docker

June 6, '17 Comments [17] Posted in Docker | DotNetCore
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“Container Ship” by NOAA's National Ocean Service is licensed under CC BY 2.0.NET and .NET Core (and Windows!) have been getting better and better with Docker. I run Docker for Windows as it supports both Linux Containers and Windows Containers. They have both a Stable and Edge channel. The Edge (Beta) channel is regularly updated and, as a rule, gets better and better in the year I've been running it.

As a slightly unrelated side note, I'm also running Docker on my Synology NAS with a number of containers, as well as .NET Core (my Nas is an Intel chip), Minecraft Server, Plex Server, and CrashPlan.

NOTE: Docker for Windows requires 64bit Windows 10 Pro and Microsoft Hyper-V. Please see What to know before you install for a full list of prerequisites.

The .NET Team at Microsoft has been getting their dockerfiles in order and organized. It can seem initially the opposite, with lots of cryptic tags and names, but there's a clear method you can read about here.

They publish their Docker images in a few different repositories on Docker Hub. It’s important to segment images so that they are easier to find, both on the Docker Hub website as well as with the docker search command.

There's also some samples at:

The samples are super easy to try out - STOP READING AND TRY THIS NOW. ;)

I'm always impressed with a nice asynchronous ASCII Progress bar. I'm easy to impress. This is a "hello world" sample with a surprise ASCII art. I won't spoil for you.

C:\Users\scott\Desktop> docker run microsoft/dotnet-samples
Unable to find image 'microsoft/dotnet-samples:latest' locally
latest: Pulling from microsoft/dotnet-samples
10a267c67f42: Downloading [========> ] 9.19MB/52.58MB
7e1a7ec87c21: Downloading [======================> ] 10.8MB/18.59MB
923d0cd2ed37: Download complete
7c523004cf83: Downloading [=========> ] 6.144MB/33.07MB
f3582118a43a: Waiting
c27ef6b597a0: Waiting

All the images are managed and maintained on GitHub so you can get involved if you're not digging the images or files.

One interesting thing to point out is the difference between dev images and production images, as well as images you'd use in CI/CD (Build Server) situations to build other images. Here are some examples from GitHub:


  • dotnetapp-dev - This sample is good for development and building since it relies on the .NET Core SDK image. It performs dotnet commands on your behalf, reducing the time it takes to create Docker images (assuming you make changes and then test them in a container, iteratively).


  • dotnetapp-prod - This sample is good for production since it relies on the .NET Core Runtime image, not the larger .NET Core SDK image. Most apps only need the runtime, reducing the size of your application image.
  • dotnetapp-selfcontained - This sample is also good for production scenarios since it relies on an operating system image (without .NET Core). Self-contained .NET Core apps include .NET Core as part of the app and not as a centrally installed component in a base image.
  • dotnetapp-current - This sample demonstrates how to configure an application to use the .NET Core 1.1 image. Both the .csproj and the Dockerfile have been updated to depend on .NET Core 1.1. This sample is the same as dotnetapp-prod with the exception of relying on a later .NET Core version.
  • aspnetapp - This samples demonstrates a Dockerized ASP.NET Core Web App

There's great Docker support in VS Code, Visual Studio 2017, and Visual Studio for Mac (the Preview channel). With VS and Docker on Windows you can even F5 (debug) into a Linux Container.

Some of you may have .NET Framework apps running in Virtual Machines that you'd love to get moved over to a container infrastructure. There's a tool called Image2Docker that Docker maintains that might help. It helps migrate VMs to Containers. Check out the Image2Docker DockerCon talk or read Docker’s Convert ASP.NET Web Servers To Docker with ImageDocker to learn more.

“Container Ship” by NOAA's National Ocean Service is licensed under CC BY 2.0

Sponsor: Check out Seq: simple centralized logging, on your infrastructure, with great support for ASP.NET Core and Serilog. Download version 4.0.

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Visual Studio and IIS Error: Specified argument was out of the range of valid values. Parameter name: site

June 3, '17 Comments [6] Posted in Bugs | IIS
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I got a very obscure and obtuse error running an ASP.NET application under Visual Studio and IIS Express recently. I'm running a Windows 10 Insiders (Fast Ring) build, so it's likely an issue with that, but since I was able to resolve the issue simply, I figured I'd blog it for google posterity .

I would run the ASP.NET app from within Visual Studio and get this totally useless error. It was happening VERY early in the bootstrapping process and NOT in my application. It pretty clearly is happening somewhere in the depths of IIS Express, perhaps in a configurator in HttpRuntime.

Specified argument was out of the range of valid values.
Parameter name: site

I fixed it by going to Windows Features and installing "IIS Hostable Web Core," part of Internet Information Services. I did this in an attempt to "fix whatever's wrong with IIS Express."

Turn Windows Features on or off

That seems to "repair" IIS Express. I'll update this post if I learn more, but hopefully if you got to this post, this fixed it for you also.

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About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.