root@ig1-k8smaster-01:~# kubectl -n kube-system logs kube-dns-4101612645-2nfs6 --container kubedns
I0419 13:56:12.853687 1 dns.go:42] version: v1.6.0-alpha.0.680+3872cb93abf948-dirty
I0419 13:56:12.854209 1 server.go:107] Using https://10.152.183.1:443 for kubernetes master, kubernetes API: <nil>
I0419 13:56:12.855212 1 server.go:68] Using configuration read from ConfigMap: kube-system:kube-dns
I0419 13:56:12.855260 1 server.go:113] FLAG: --alsologtostderr="false"
I0419 13:56:12.855285 1 server.go:113] FLAG: --config-map="kube-dns"
I0419 13:56:12.855297 1 server.go:113] FLAG: --config-map-namespace="kube-system"
I0419 13:56:12.855305 1 server.go:113] FLAG: --dns-bind-address="0.0.0.0"
I0419 13:56:12.855312 1 server.go:113] FLAG: --dns-port="10053"
I0419 13:56:12.855323 1 server.go:113] FLAG: --domain="cluster.local."
I0419 13:56:12.855333 1 server.go:113] FLAG: --federations=""
I0419 13:56:12.855342 1 server.go:113] FLAG: --healthz-port="8081"
I0419 13:56:12.855350 1 server.go:113] FLAG: --kube-master-url=""
I0419 13:56:12.855359 1 server.go:113] FLAG: --kubecfg-file=""
I0419 13:56:12.855365 1 server.go:113] FLAG: --log-backtrace-at=":0"
I0419 13:56:12.855375 1 server.go:113] FLAG: --log-dir=""
I0419 13:56:12.855383 1 server.go:113] FLAG: --log-flush-frequency="5s"
I0419 13:56:12.855393 1 server.go:113] FLAG: --logtostderr="true"
I0419 13:56:12.855402 1 server.go:113] FLAG: --stderrthreshold="2"
I0419 13:56:12.855409 1 server.go:113] FLAG: --v="0"
I0419 13:56:12.855416 1 server.go:113] FLAG: --version="false"
I0419 13:56:12.855427 1 server.go:113] FLAG: --vmodule=""
I0419 13:56:12.855575 1 server.go:155] Starting SkyDNS server (0.0.0.0:10053)
I0419 13:56:12.855901 1 server.go:165] Skydns metrics enabled (/metrics:10055)
I0419 13:56:12.856468 1 logs.go:41] skydns: ready for queries on cluster.local. for tcp://0.0.0.0:10053 [rcache 0]
I0419 13:56:12.856501 1 logs.go:41] skydns: ready for queries on cluster.local. for udp://0.0.0.0:10053 [rcache 0]
I0419 13:56:20.329377 1 logs.go:41] skydns: failure to forward request "read udp 10.1.80.6:45349->10.3.255.1:53: i/o timeout"
I0419 13:56:35.342191 1 logs.go:41] skydns: failure to forward request "read udp 10.1.80.6:47128->10.3.255.1:53: i/o timeout"