Currently if we define taints on all node pools in a cluster then nodelocaldns pods wont get scheduled on those node pools. Also in GKE as the daemonset has reconcile flag set tolerations cannot be added. So adding these tolerations will allow nodelocaldns pods to get scheduled on all node pools.
NodeLocalDNS addon listens on both DNS_SERVER_IP as well as LOCAL_DNS_IP. So cluster-dns flag can continue to be DNS_SERVER_IP in all cases.
Documented the various variables in the yaml.
Similar to `--no-negcache` on dnsmasq, this prevents issues which poll DNS for orchestration such as operators with StatefulSets. It can also be very confusing for users when negative caching results in a change they just made seeming to be broken until the cache expires. This assumes that 5 seconds is reasonable and will still catch repeated AAAA negative responses. We could also set the denial cache size to zero which should effectively fully disable it like dnsmasq in kube-dns but testing shows this approach seems to work well in our (albeit small) test clusters.
This change includes the yaml files and gce startup script changes
to run this addon. It is disabled by default, can be enabled by setting
KUBE_ENABLE_NODELOCAL_DNS=true
An ip address is required for the cache instance to listen for
requests on, default is a link local ip address of value 169.254.25.10
addressed review comments, updated image location
Picked a different prometheus port so stats port is not same as the
coredns deployment
Removed the nodelocaldns-ready label.
Set memory limit to 30Mi
