---
title: "Run a .NET App"
layout: language-and-framework-docs
redirect_from: /docs/getting-started/dotnet/
---
<%= partial "partials/intro", locals: { runtime: "[.NET](https://dotnet.microsoft.com/)" } %>
## _Generate the .NET Application_
For our example, we will create a simple "hello world" application using the default web template in .NET. We assume that you have already installed [.NET](https://dotnet.microsoft.com/en-us/download).
Once .NET is installed, we can create a new project by running the following command:
```cmd
dotnet new web --name hellodotnet
```
```output
The template "ASP.NET Core Empty" was created successfully.
Processing post-creation actions...
Restoring \hellodotnet\hellodotnet.csproj:
Determining projects to restore...
Restored \hellodotnet\hellodotnet.csproj (in 69 ms).
Restore succeeded.
```
## _Running the Application_
In the new application folder, execute the command `dotnet run` to initiate the application:
```cmd
dotnet run
```
```output
Building...
Now listening on: http://localhost:5162
Application started. Press Ctrl+C to shut down.
Hosting environment: Development
```
This command will start the "hellodotnet" application, and you will be able to access it locally using the address provided in the output.
Now, let's proceed to deploy this application to Fly.
## _Install Flyctl and Login_
We are ready to start working with Fly.io, and that means we need `flyctl`, our CLI app for managing apps on Fly.io. If you've already installed it, carry on. If not, hop over to [our installation guide](/docs/flyctl/install/). Once that's installed you'll want to [log in to Fly.io](/docs/getting-started/sign-up-sign-in/).
## _Launch the app on Fly_
Each Fly App needs a `fly.toml` file to tell the system how we'd like to deploy it.
That file can be automatically generated with the command `flyctl launch` command. This command will also generate a Dockerfile for deployment.
```cmd
fly launch
```
```output
Creating app in \fly\guides\hellodotnet
Scanning source code
Detected a .NET app
? Choose an app name (leave blank to generate one): hellodotnet
? Select Organization: demo (demo)
? Select region: ord (Chicago, Illinois (US))
App will use 'ord' region as primary
Created app 'hellodotnet' in organization 'demo'
Admin URL: https://fly.io/apps/hellodotnet
Hostname: hellodotnet.fly.dev
? Would you like to set up a Postgresql database now? No
? Would you like to set up an Upstash Redis database now? No
Wrote config file fly.toml
? Would you like to deploy now? Yes
Deploying hellodotnet
...
```
That's it! Run `fly apps open` to see your deployed app in action.
Try a few other commands:
- `fly logs` - Tail your application logs
- `fly status` - App deployment details
- `fly deploy` - Deploy the application after making changes
## _Inside `fly.toml`_
The `fly.toml` file now contains a default configuration for deploying your app. In the process of creating that file, `flyctl` has also created a Fly-side application slot of the same name, "hellodotnet". If we look at the `fly.toml` configuration file we can see the name in there:
```toml
app = "hellodotnet"
primary_region = "ord"
[http_service]
internal_port = 8080
force_https = true
auto_stop_machines = true
auto_start_machines = true
min_machines_running = 0
processes = ["app"]
...
```
The `flyctl` command will always refer to this file in the current directory if it exists, specifically for the `app` name/value at the start. That name will be used to identify the application to the Fly.io platform.
The rest of the file contains settings to be applied to the application when it deploys.
## Deploying to Fly.io
To deploy changes to your app, just run just run:
```cmd
fly deploy
```
This will lookup our `fly.toml` file and get the app name `hellodotnet` from there.
Then `flyctl` will start the process of deploying our application to Fly.io using the Dockerfile. Flyctl will return you to the command line when it's done.
## _Viewing the Deployed App_
If you want to find out more about the deployment. The command `fly status` will give you all the essential details.
```cmd
fly status
```
```output
App
Name = hellodotnet
Owner = personal
Hostname = hellodotnet.fly.dev
Image = hellodotnet:deployment-01H4MDR3GVFX20X5DNVZS4BPWK
Platform = machines
Machines
PROCESS ID VERSION REGION STATE CHECKS LAST UPDATED
app 91857500000083 1 ord started 2023-07-06T01:49:28Z
app e2865100000086 1 ord stopped 2023-07-06T01:50:04Z
```
## _Connecting to the App_
The quickest way to browse your newly deployed application is with the `flyctl apps open` command.
```cmd
flyctl apps open
```
```output
Opening https://hellodotnet.fly.dev/
```
Your browser will be sent to the displayed URL.
## _Bonus Points_
If you want to know what IP addresses the app is using, try `fly ips list`:
```cmd
fly ips list
```
```out
VERSION IP TYPE REGION CREATED AT
v6 2a09:8280:1::69:37fd public global 18m55s ago
v4 66.241.125.223 public (shared)
```
## Arrived at Destination
You have successfully built, deployed, and connected to your first .NET web application on Fly.io.
Run a .NET App
Getting an application running on Fly.io is essentially working out how to package it as a deployable image.
Once packaged, it can be deployed to the Fly.io platform.
In this guide we’ll learn how to deploy a .NET
application
on Fly.io.
Generate the .NET Application
For our example, we will create a simple “hello world” application using the default web template in .NET. We assume that you have already installed .NET.
Once .NET is installed, we can create a new project by running the following command:
dotnet new web --name hellodotnet
The template "ASP.NET Core Empty" was created successfully.
Processing post-creation actions...
Restoring \hellodotnet\hellodotnet.csproj:
Determining projects to restore...
Restored \hellodotnet\hellodotnet.csproj (in 69 ms).
Restore succeeded.
Running the Application
In the new application folder, execute the command dotnet run to initiate the application:
dotnet run
Building...
Now listening on: http://localhost:5162
Application started. Press Ctrl+C to shut down.
Hosting environment: Development
This command will start the “hellodotnet” application, and you will be able to access it locally using the address provided in the output.
Now, let’s proceed to deploy this application to Fly.
Install Flyctl and Login
We are ready to start working with Fly.io, and that means we need flyctl, our CLI app for managing apps on Fly.io. If you’ve already installed it, carry on. If not, hop over to our installation guide. Once that’s installed you’ll want to log in to Fly.io.
Launch the app on Fly
Each Fly App needs a fly.toml file to tell the system how we’d like to deploy it.
That file can be automatically generated with the command flyctl launch command. This command will also generate a Dockerfile for deployment.
fly launch
Creating app in \fly\guides\hellodotnet
Scanning source code
Detected a .NET app
? Choose an app name (leave blank to generate one): hellodotnet
? Select Organization: demo (demo)
? Select region: ord (Chicago, Illinois (US))
App will use 'ord' region as primary
Created app 'hellodotnet' in organization 'demo'
Admin URL: https://fly.io/apps/hellodotnet
Hostname: hellodotnet.fly.dev
? Would you like to set up a Postgresql database now? No
? Would you like to set up an Upstash Redis database now? No
Wrote config file fly.toml
? Would you like to deploy now? Yes
Deploying hellodotnet
...
That’s it! Run fly apps open to see your deployed app in action.
Try a few other commands:
fly logs - Tail your application logs
fly status - App deployment details
fly deploy - Deploy the application after making changes
Inside fly.toml
The fly.toml file now contains a default configuration for deploying your app. In the process of creating that file, flyctl has also created a Fly-side application slot of the same name, “hellodotnet”. If we look at the fly.toml configuration file we can see the name in there:
The flyctl command will always refer to this file in the current directory if it exists, specifically for the app name/value at the start. That name will be used to identify the application to the Fly.io platform.
The rest of the file contains settings to be applied to the application when it deploys.
Deploying to Fly.io
To deploy changes to your app, just run just run:
fly deploy
This will lookup our fly.toml file and get the app name hellodotnet from there.
Then flyctl will start the process of deploying our application to Fly.io using the Dockerfile. Flyctl will return you to the command line when it’s done.
Viewing the Deployed App
If you want to find out more about the deployment. The command fly status will give you all the essential details.
fly status
App
Name = hellodotnet
Owner = personal
Hostname = hellodotnet.fly.dev
Image = hellodotnet:deployment-01H4MDR3GVFX20X5DNVZS4BPWK
Platform = machines
Machines
PROCESS ID VERSION REGION STATE CHECKS LAST UPDATED
app 91857500000083 1 ord started 2023-07-06T01:49:28Z
app e2865100000086 1 ord stopped 2023-07-06T01:50:04Z
Connecting to the App
The quickest way to browse your newly deployed application is with the flyctl apps open command.
flyctl apps open
Opening https://hellodotnet.fly.dev/
Your browser will be sent to the displayed URL.
Bonus Points
If you want to know what IP addresses the app is using, try fly ips list:
fly ips list
VERSION IP TYPE REGION CREATED AT
v6 2a09:8280:1::69:37fd public global 18m55s ago
v4 66.241.125.223 public (shared)
Arrived at Destination
You have successfully built, deployed, and connected to your first .NET web application on Fly.io.