Missing CNI plugins binaries

[Danilo Riecken de Morais]

I think the tutorial to install Kubernetes in Container Linux is missing a step. The step by step tutorial does not mention anything about the following situation:

After installing the Kubernetes cluster using the tutorial, the pods fail to start with the following messages:

Events:
  FirstSeen	LastSeen	Count	From			SubObjectPath	Type		Reason		Message
  ---------	--------	-----	----			-------------	--------	------		-------
  6m		6m		1	default-scheduler			Normal		Scheduled	Successfully assigned mypodXXXX to x.x.x.x
  6m		3m		117	kubelet, x.x.x.x			Warning		FailedSync	Error syncing pod, skipping: failed to "SetupNetwork" for "mypodXXXX" with SetupNetworkError: "Failed to setup network for pod \"mypodXXXX\" using network plugins \"cni\": failed to find plugin \"loopback\" in path [/opt/loopback/bin /opt/cni/bin]; Skipping pod"

  3m	2s	224	kubelet, x.x.x.x		Warning	FailedSync	Error syncing pod, skipping: failed to "SetupNetwork" for "mypodXXXX" with SetupNetworkError: "Failed to setup network for pod \"mypodXXXX\" using network plugins \"cni\": failed to find plugin \"bridge\" in path [/opt/cni/bin /opt/flannel/bin]; Skipping pod"

After manually downloading the cni plugin binaries v0.4.0 package from https://github.com/containernetworking/cni/releases/tag/v0.4.0 and unpacking it to /opt/cni/bin
the pods deploy correctly.

More details:

Operating System: Container Linux by CoreOS stable (1353.7.0)
Tutorial Version 1.5.4
Kubernetes Version 1.5.4

[Krzysztof Gajdemski]

You actually don't have to manually download CNI plugins. They are embedded in hypercube images. If you just remove following lines from the kubelet.service CNI should work fine:

--volume cni-bin,kind=host,source=/opt/cni/bin \
--mount volume=cni-bin,target=/opt/cni/bin

But obviously the tutorial is (was?) wrong requesting mounting cni-bin volume. It is only necessary when you want to alter plugin set.