sccache: error: Timed out waiting for server startup

[crohr]

Recently switched to RunsOn and when using S3 backend for sccache with RunsOn, occasionally I'm getting the following failure when running cargo commands:

sccache: error: Timed out waiting for server startup. Maybe the remote service is unreachable?
Run with SCCACHE_LOG=debug SCCACHE_NO_DAEMON=1 to get more information

Those are the relevant steps in the job:

    - name: Setup RunsOn
      uses: runs-on/action@v2.0.3
      with:
        show_env: false
        show_costs: false
        sccache: s3

    - name: Start sccache
      uses: mozilla-actions/sccache-action@v0.0.9

The steps are executed in a container scope (there were no issues on GHA managed runners).This happens on ARM64 as well as AMD64 runners.

• ubuntu24-full-ARCH RunsOn image is used.

• extras=s3-cache is set.