How to determine if asp.net core has been installed on a windows server

Question

I'm setting up various windows servers to host asp.net core apps, and I need to be able to determine if they have the asp.net hosting bundle installed.

https://docs.asp.net/en/latest/publishing/iis.html#install-the-net-core-windows-server-hosting-bundle says:

"Install the .NET Core Windows Server Hosting bundle on the server. The bundle will install the .NET Core Runtime, .NET Core Library, and the ASP.NET Core Module. The module creates the reverse-proxy between IIS and the Kestrel server."

I'm setting up a deployment, and I need to make sure my server is configured so I can run asp.net core apps.

I'm looking, basically, for a registry key or some other way to tell me if I should run the installer setup. (something like the way we'd tell if older versions of the framework are installed, like https://support.microsoft.com/en-us/kb/318785 does for earlier versions)

Answer 1

You can use powershell to check if the hosting module is registered with IIS

In the local powershell session

Import-module WebAdministration
$vm_dotnet_core_hosting_module = Get-WebGlobalModule | where-object { $_.name.ToLower() -eq "aspnetcoremodule" }
if (!$vm_dotnet_core_hosting_module)
{
    throw ".Net core hosting module is not installed"
}

If you want to do in the remote session replace first 2 lines with

Invoke-Command -Session $Session {Import-module WebAdministration}
$vm_dotnet_core_hosting_module = Invoke-Command -Session $Session {Get-WebGlobalModule | where-object { $_.name.ToLower() -eq "aspnetcoremodule" }}

Answer 2

You can search Microsoft .NET Core 1.1.1 - Windows Server Hosting registry key under HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Updates\.NET Core path like screenshot below.

Also you can use PowerShell to determine the whether the key existed or not.

$DotNETCoreUpdatesPath = "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Updates\.NET Core"
$DotNetCoreItems = Get-Item -ErrorAction Stop -Path $DotNETCoreUpdatesPath
$NotInstalled = $True
$DotNetCoreItems.GetSubKeyNames() | Where { $_ -Match "Microsoft .NET Core.*Windows Server Hosting" } | ForEach-Object {
    $NotInstalled = $False
    Write-Host "The host has installed $_"
}
If ($NotInstalled) {
    Write-Host "Can not find ASP.NET Core installed on the host"
}

And you can download sample from How to determine ASP.NET Core installation on a Windows Server by PowerShell.

Answer 3

If you have .NET Core CLI installed, you can try:

dotnet --list-runtimes

Which will print something like:

Microsoft.NETCore.App 3.0.0 [c:\program files\dotnet\shared\Microsoft.NETCore.App] Microsoft.NETCore.App 3.1.0 [c:\program files\dotnet\shared\Microsoft.NETCore.App]

Reference: Microsoft doc

Answer 4

If you're allowed to introduce constraints, one option is to only allow "Self-contained applications" since they do not require any additional installs. This also makes issues like 'what version is installed' go away.

If you need to support 'portable apps' you could simply execute the following to check if dotnet.exe is available:

where dotnet

You can then check the version:

dotnet --version

This would also allow you to check the version of .NET Core once that becomes a concern.

Answer 5

Note that the commands need to be run in powershell as Administrator.

Using the IISAdministration powershell module all modules can be listed as follows:

Import-Module IISAdministration

(Get-IISConfigSection -SectionPath "system.webServer/globalModules" `
| Get-IISConfigCollection).GetCollection() `
| select @{n="name";e={$_.GetAttributeValue("name")}}, `
         @{n="image";e={$_.GetAttributeValue("image")}}, `
         @{n="preCondition";e={$_.GetAttributeValue("preCondition")}}

So a test could be e.g.

$coreModule =
(Get-IISConfigSection -SectionPath "system.webServer/globalModules" `
| Get-IISConfigCollection).GetCollection() `
| where {$_.GetAttributeValue("name") -eq "AspNetCoreModuleV2" }

if (-not $coreModule)
{
    throw 'AspNetCoreModuleV2 is not installed'
}

Note at the time of this writing, both AspNetCoreModule and AspNetcoreModuleV2 are listed separately. Additional versions will likely show up in the future.

Answer 6

You can also double click DotNetCore.1.0.1-WindowsHosting.exe
If the .NET Core Windows Server Hosting bundle is already installed, the opening window will have :

1. Modify Setup label
2. Repair and Uninstall buttons

Repair and Uninstall buttons and a Modify Setup label.

Answer 7

You can look at

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall{ab4f6e29-67a1-47d9-b2ab-43348a9bbae4}

and make sure that "Microsoft .NET Core 1.0.0 - Windows Server Hosting" is there