connectivity: Start with initial DNS check #716
Description
When basic connectivity across nodes is not working, the connectivity tests often fail with:
$ ./cilium connectivity test --namespace cilium
⌛ [test-ipsec-1] Waiting for deployments [client client2 echo-same-node] to become ready...
⌛ [test-ipsec-1] Waiting for deployments [echo-other-node] to become ready...
⌛ [test-ipsec-1] Waiting for CiliumEndpoint for pod cilium-test/client-7b7bf54b85-nrpzc to appear...
⌛ [test-ipsec-1] Waiting for CiliumEndpoint for pod cilium-test/client2-666976c95b-pnwq4 to appear...
⌛ [test-ipsec-1] Waiting for CiliumEndpoint for pod cilium-test/echo-other-node-697d5d69b7-t92s9 to appear...
⌛ [test-ipsec-1] Waiting for CiliumEndpoint for pod cilium-test/echo-same-node-7967996674-spmhf to appear...
⌛ [test-ipsec-1] Waiting for Service cilium-test/echo-other-node to become ready...
Error: Connectivity test failed: timeout reached waiting for {&Service{ObjectMeta:{echo-other-node cilium-test 36ecfddc-3948-44dd-a9fa-30aa1f3c2d9a 10812171 0 2022-02-17 23:50:02 +0100 CET <nil> <nil> map[kind:echo] map[] [] [] [{cilium Update v1 2022-02-17 23:50:02 +0100 CET FieldsV1 {"f:metadata":{"f:labels":{".":{},"f:kind":{}}},"f:spec":{"f:externalTrafficPolicy":{},"f:ports":{".":{},"k:{\"port\":8080,\"protocol\":\"TCP\"}":{".":{},"f:name":{},"f:port":{},"f:protocol":{},"f:targetPort":{}}},"f:selector":{".":{},"f:name":{}},"f:sessionAffinity":{},"f:type":{}}}}]},Spec:ServiceSpec{Ports:[]ServicePort{ServicePort{Name:echo-other-node,Protocol:TCP,Port:8080,TargetPort:{0 8080 },NodePort:30721,AppProtocol:nil,},},Selector:map[string]string{name: echo-other-node,},ClusterIP:10.0.142.235,Type:NodePort,ExternalIPs:[],SessionAffinity:None,LoadBalancerIP:,LoadBalancerSourceRanges:[],ExternalName:,ExternalTrafficPolicy:Cluster,HealthCheckNodePort:0,PublishNotReadyAddresses:false,SessionAffinityConfig:nil,TopologyKeys:[],IPFamilyPolicy:nil,ClusterIPs:[10.0.142.235],IPFamilies:[],AllocateLoadBalancerNodePorts:nil,LoadBalancerClass:nil,InternalTrafficPolicy:nil,},Status:ServiceStatus{LoadBalancer:LoadBalancerStatus{Ingress:[]LoadBalancerIngress{},},Conditions:[]Condition{},},}}
This is because DNS resolution doesn't work.
We could do a better job at highlighting the actual issue here, rather than sending a rather cryptic message.