Description
NPD can be configured to run in either standalone or daemonset mode. In k/k, the NPD standalone mode can be configured and tested by configure.sh#688. However, as part of the kops support, the default mode has been switched from standalone mode to daemonset mode in PR kubernetes/kubernetes#121007. The PR also bumped NPD version from v0.8.9 to v0.8.13.
On the other hand, NPD standalone mode test has always been relying on tar files in gs://kubernetes-release/node-problem-detector/ historically (See configure.sh#L29). And we only have NPD version up to v0.8.10 in the GCS bucket, due to historical release problems. This means we do not even have v0.8.13 tar files in the GCS. Given none of the k/k's release blocking tests fail, we lost the test coverage for standalone mode configuration already.
The release problem is being tracked by #874. We were trying to switch from using gs://kubernetes-release/ to github's own file hosting (PR kubernetes/kubernetes#123741) and realized the missing test coverage.