Use hostNetwork for vpcrouter #172
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jbrendel
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Aug 18, 2017
cgilmour
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Changes to support kubeadm 1.9
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The vpcrouter tool uses the AWS API endpoints to make changes to the routing tables within a VPC.
To look up the API endpoint, it needs DNS.
However, kube-dns runs as a service, and some of the the pods providing that service might be running in a different region before vpcrouter has created the routes to access pods there.
It isn't immediately noticeable in some installs, because the first instance of kube-dns runs on a directly-reachable master node.
It becomes a problem when kube-dns is scaled up to more pods - some reachable, some not.
This PR changes the vpcrouter pod to use
hostNetwork: trueto ensure it is always able to look up the AWS API endpoint addresses and bring the pod network into a fully routed state.