Ubuntu image 24.04 .NET version

[tibitoth]

Description

ubuntu 24.04 image contains .NET SDK 8.0.114, see: https://github.com/actions/runner-images/blob/main/images/ubuntu/Ubuntu2404-Readme.md

while ubuntu 22.04 image contains the newer .NET SDK 8.0.407, see: https://github.com/actions/runner-images/blob/main/images/ubuntu/Ubuntu2204-Readme.md

Platforms affected

• Azure DevOps
• GitHub Actions - Standard Runners
• GitHub Actions - Larger Runners

Runner images affected

• Ubuntu 20.04
• Ubuntu 22.04
• Ubuntu 24.04
• macOS 13
• macOS 13 Arm64
• macOS 14
• macOS 14 Arm64
• macOS 15
• macOS 15 Arm64
• Windows Server 2019
• Windows Server 2022
• Windows Server 2025

Image version and build link

Is it regression?

22.04

Expected behavior

24.04 should contain .NET SDK 8.0.407

Actual behavior

24.04 now contains .NET SDK 8.0.114

Repro steps

build .NET app with global.json which requires 8.0.4xx SDK

[vidyasagarnimmagaddi]

Hi @tibitoth , Thank you for bringing this issue to our attention. We will look into this issue and will update you after investigating.


[Ilia-Kosenkov]

This also broke our source generator

##[warning]CSC(0,0): Warning CS9057: The analyzer assembly '/home/vsts/.nuget/packages/<generator-name>/1.1.0/analyzers/dotnet/cs/<generator-name>.dll' references version '4.10.0.0' of the compiler, which is newer than the currently running version '4.8.0.0'.

This requires SDK 8.0.3xx, when you ship 8.0.1xx. According to this 8.0.1xx was released in Nov'23, and we are in Apr'25.

[jamesbascle]

Please fix this....dozens of pipelines broke overnight.

[tibitoth]

Also, there was a new .NET SDK release yesterday: dotnet/announcements#353
So, the latest version should be 8.0.408 from now

[tibitoth]

You can use the following workarounds until it get fixed:

1. use ubuntu-2204 instead of ubuntu-latest
2. use .NET SDK install task to install 8.0.4xx SDK

[hemanthmanga]

Hi @tibitoth, FYI, Ubuntu 22 and Ubuntu 24 are different images, and the .NET versions will be updated from different release sources—Jammy Jellyfish for Ubuntu 22 and Noble Numbat for Ubuntu 24. As you mentioned, if you require .NET 8.0.4xx, use Ubuntu 22, and if you need 8.0.1xx, use Ubuntu 24. However, Please don’t expect the same .NET versions or patches when comparing the two images.

[Sharparam]

I would say it's reasonable to assume a newer OS image should have a newer version of .NET (or at least not downgrade it).

Also, according to Ubuntu's own package search, jammy uses 8.0.115 (https://packages.ubuntu.com/jammy/dotnet-sdk-8.0). So Microsoft must be doing something custom to replace it with a newer version in the 22.04 image. Shouldn't the same fix be done in the 24.04 image then?

[hemanthmanga]

I would say it's reasonable to assume a newer OS image should have a newer version of .NET (or at least not downgrade it).

Also, according to Ubuntu's own package search, jammy uses 8.0.115 (https://packages.ubuntu.com/jammy/dotnet-sdk-8.0). So Microsoft must be doing something custom to replace it with a newer version in the 22.04 image. Shouldn't the same fix be done in the 24.04 image then?

Hi @Sharparam, @tibitoth
You're correct, it makes sense to assume new OS versions like Ubuntu 24.04 would include newer versions of .NET SDK than those of older versions like 22.04. But a key point regarding GitHub-hosted runners.

GitHub runners don't depend exclusively on the.NET SDK versions available through the OS. Instead, it focus on having the newest SDKs in order to assist developers with new features or the latest patches. To accomplish this, runners get the latest official SDK versions directly from Microsoft, instead of waiting for Ubuntu's packaging cycle.Please refer to the relevant issue and document for more details. we are closing this issue. Thanks!

[Sharparam]

A sad conclusion as that means adding up to several minutes to the build time of our projects (for the manual SDK install step) just to get an actually up to date version of the SDK :/