Update build containers

[richlander]

The following container references need to be updated in all active branches.

aspnetcore/.azure/pipelines/ci.yml

Lines 129 to 133 in a4ca931

	image: mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.19-WithNode
	mariner20CrossArmAlpine:
	image: mcr.microsoft.com/dotnet-buildtools/prereqs:cbl-mariner-2.0-cross-arm-alpine
	mariner20CrossArm64Alpine:
	image: mcr.microsoft.com/dotnet-buildtools/prereqs:cbl-mariner-2.0-cross-arm64-alpine

There are two issues at play:

• Mariner 2.0 is going away in June. We need to remove all references to it before then.
• We have adopted new schemes for build images.
  • https://github.com/dotnet/runtime/blob/main/docs/workflow/using-docker.md
  • https://github.com/dotnet/runtime/blob/release/8.0/docs/workflow/building/coreclr/linux-instructions.md#docker-images
  • We no longer produce the WithNode Alpine variant
  • Do you need runtime build images? Is a regular SDK image sufficient or are you building native code?

Related: dotnet/runtime#112191

[richlander]

@sbomer @jkoritzinsky @mthalman @wtgodbe

[wtgodbe]

We don't build native components in those jobs, but the legs using those containers do build node components, so we'd need containers w/ node installed to replace them

[richlander]

Should we create a pre-req container that is the .NET SDK + node + Helix?

Is this for building? It looks like that, but I want to confirm. Also, do you really need a cross image? I assume not.

[wtgodbe]

Yes, we use the images for building - .NET SDK + node should be sufficient for that. If it was suitable for Helix that'd be nice too as we could use it in multiple places, but wouldn't be necessary for the way we use those containers today.

I don't think we need a cross image - we just need images we can build our musl bits on.

[richlander]

You are right. Helix isn't needed. I was getting my wires crossed.

I assume you install the SDK with the install script per the global.json for the branch. Do you just need an image that has .NET dependencies + node in it?

[wtgodbe]

I assume you install the SDK with the install script per the global.json for the branch. Do you just need an image that has .NET dependencies + node in it?

Yes, that should be sufficient

[richlander]

I'll make something and let's give it a try.

[richlander]

Do you think we can get away with a single container image? Specifically, do you need an Alpine variant? Is an Azure Linux x64 image sufficient?

[wtgodbe]

Do you think we can get away with a single container image? Specifically, do you need an Alpine variant? Is an Azure Linux x64 image sufficient?

Having an Alpine variant is nice as that way we can build our musl bits on a musl image - but it's not strictly necessary. I'm fine cross-building if we're trying to slim down our set of docker images.

[richlander]

I'd much prefer we built everything in Azure Linux images, like we do for runtime. Sounds like it is just a change in approach. If it is a big deal, let's take a closer look. I'll make the Azure Linux image later today.

[richlander]

Can you give this a shot @wtgodbe? This is beyond my ability to do efficiently.

Here's the new image: mcr.microsoft.com/dotnet-buildtools/prereqs:azurelinux-3.0-net10.0-build-amd64