У меня два идентичных pod
, работающих на двух рабочих узлах, которые обслуживаются извне через svc
.следующим образом:
root@master1:~# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
kubia-nwjcc 1/1 Running 0 33m 10.244.1.27 worker1
kubia-zcpbb 1/1 Running 0 33m 10.244.2.11 worker2
root@master1:~# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 26h
kubia ClusterIP 10.98.41.49 <none> 80/TCP 34m
Но когда я пытаюсь получить доступ к svc
в одном из pod
, я могу получить ответ pod
только на том же узле.Когда svc обращается к pod
на другом узле.Когда svc
пытается получить доступ к pod
на других узлах, он вернет command terminated with exit code 7
.правильный вывод и неправильный вывод генерируются случайным образом, как показано ниже:
правильный вывод
root@master1:~# k exec kubia-nwjcc -- curl http://10.98.41.49
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 23 0 23 0 0 8543 0 --:--:-- --:--:-- --:--:-- 11500
You've hit kubia-nwjcc
неверный вывод
root@master1:~# kubectl exec kubia-nwjcc -- curl http://10.98.41.49
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0
curl: (7) Failed to connect to 10.98.41.49 port 80: No route to host
command terminated with exit code 7
Ниже приводится версия программного обеспечения, которую я использую:
- ubuntu:
v18.04
- kubelet / kubeadm / kubectl:
v1.15.0
- docker:
v18.09.5
Ниже приведено svc
описание:
root@master1:~# kubectl describe svc kubia
Name: kubia
Namespace: default
Labels: <none>
Annotations: <none>
Selector: app=kubia
Type: ClusterIP
IP: 10.98.41.49
Port: <unset> 80/TCP
TargetPort: 8080/TCP
Endpoints: 10.244.1.27:8080,10.244.2.11:8080
Session Affinity: None
Events: <none>
Ниже приведены возвращаемые результаты с использованием -v=9
:
root@master1:~# kubectl exec kubia-nwjcc -v=9 -- curl -s http://10.98.41.49
I0702 11:45:52.481239 23171 loader.go:359] Config loaded from file: /root/.kube/config
I0702 11:45:52.501154 23171 round_trippers.go:419] curl -k -v -XGET -H "Accept: application/json, */*" -H "User-Agent: kubectl/v1.15.0 (linux/amd64) kubernetes/e8462b5" 'https://192.168.56.11:6443/api/v1/namespaces/default/pods/kubia-nwjcc'
I0702 11:45:52.525926 23171 round_trippers.go:438] GET https://192.168.56.11:6443/api/v1/namespaces/default/pods/kubia-nwjcc 200 OK in 24 milliseconds
I0702 11:45:52.525980 23171 round_trippers.go:444] Response Headers:
I0702 11:45:52.525992 23171 round_trippers.go:447] Content-Type: application/json
I0702 11:45:52.526003 23171 round_trippers.go:447] Content-Length: 2374
I0702 11:45:52.526012 23171 round_trippers.go:447] Date: Tue, 02 Jul 2019 11:45:52 GMT
I0702 11:45:52.526063 23171 request.go:947] Response Body: {"kind":"Pod","apiVersion":"v1","metadata":{"name":"kubia-nwjcc","generateName":"kubia-","namespace":"default","selfLink":"/api/v1/namespaces/default/pods/kubia-nwjcc","uid":"2fd67789-c48d-4459-8b03-ac562b4a3f5c","resourceVersion":"188689","creationTimestamp":"2019-07-02T10:51:34Z","labels":{"app":"kubia"},"ownerReferences":[{"apiVersion":"apps/v1","kind":"ReplicaSet","name":"kubia","uid":"f3a4c457-dee4-4aec-ad73-1f0ca41628aa","controller":true,"blockOwnerDeletion":true}]},"spec":{"volumes":[{"name":"default-token-6pgh8","secret":{"secretName":"default-token-6pgh8","defaultMode":420}}],"containers":[{"name":"kubia","image":"luksa/kubia","ports":[{"containerPort":8080,"protocol":"TCP"}],"resources":{},"volumeMounts":[{"name":"default-token-6pgh8","readOnly":true,"mountPath":"/var/run/secrets/kubernetes.io/serviceaccount"}],"terminationMessagePath":"/dev/termination-log","terminationMessagePolicy":"File","imagePullPolicy":"Always"}],"restartPolicy":"Always","terminationGracePeriodSeconds":30,"dnsPolicy":"ClusterFirst","serviceAccountName":"default","serviceAccount":"default","nodeName":"worker1","securityContext":{},"schedulerName":"default-scheduler","tolerations":[{"key":"node.kubernetes.io/not-ready","operator":"Exists","effect":"NoExecute","tolerationSeconds":300},{"key":"node.kubernetes.io/unreachable","operator":"Exists","effect":"NoExecute","tolerationSeconds":300}],"priority":0,"enableServiceLinks":true},"status":{"phase":"Running","conditions":[{"type":"Initialized","status":"True","lastProbeTime":null,"lastTransitionTime":"2019-07-03T01:35:15Z"},{"type":"Ready","status":"True","lastProbeTime":null,"lastTransitionTime":"2019-07-03T01:35:20Z"},{"type":"ContainersReady","status":"True","lastProbeTime":null,"lastTransitionTime":"2019-07-03T01:35:20Z"},{"type":"PodScheduled","status":"True","lastProbeTime":null,"lastTransitionTime":"2019-07-02T10:51:34Z"}],"hostIP":"192.168.56.21","podIP":"10.244.1.27","startTime":"2019-07-03T01:35:15Z","containerStatuses":[{"name":"kubia","state":{"running":{"startedAt":"2019-07-03T01:35:19Z"}},"lastState":{},"ready":true,"restartCount":0,"image":"luksa/kubia:latest","imageID":"docker-pullable://luksa/kubia@sha256:3f28e304dc0f63dc30f273a4202096f0fa0d08510bd2ee7e1032ce600616de24","containerID":"docker://27da556930baf857e5af92b13934dcb1b2b2f001ecab5e7b952b2bda5aa27f0b"}],"qosClass":"BestEffort"}}
I0702 11:45:52.543108 23171 round_trippers.go:419] curl -k -v -XPOST -H "X-Stream-Protocol-Version: v4.channel.k8s.io" -H "X-Stream-Protocol-Version: v3.channel.k8s.io" -H "X-Stream-Protocol-Version: v2.channel.k8s.io" -H "X-Stream-Protocol-Version: channel.k8s.io" -H "User-Agent: kubectl/v1.15.0 (linux/amd64) kubernetes/e8462b5" 'https://192.168.56.11:6443/api/v1/namespaces/default/pods/kubia-nwjcc/exec?command=curl&command=-s&command=http%3A%2F%2F10.98.41.49&container=kubia&stderr=true&stdout=true'
I0702 11:45:52.591166 23171 round_trippers.go:438] POST https://192.168.56.11:6443/api/v1/namespaces/default/pods/kubia-nwjcc/exec?command=curl&command=-s&command=http%3A%2F%2F10.98.41.49&container=kubia&stderr=true&stdout=true 101 Switching Protocols in 47 milliseconds
I0702 11:45:52.591208 23171 round_trippers.go:444] Response Headers:
I0702 11:45:52.591217 23171 round_trippers.go:447] Connection: Upgrade
I0702 11:45:52.591221 23171 round_trippers.go:447] Upgrade: SPDY/3.1
I0702 11:45:52.591225 23171 round_trippers.go:447] X-Stream-Protocol-Version: v4.channel.k8s.io
I0702 11:45:52.591229 23171 round_trippers.go:447] Date: Wed, 03 Jul 2019 02:29:33 GMT
F0702 11:45:53.783725 23171 helpers.go:114] command terminated with exit code 7
состояние kube-system
модуля и двух модулей, предоставляющих услугу, равно Running
, как указано ниже:
root@master1:~/k8s-yaml# kubectl get --all-namespaces pod -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
default kubia-6pjz9 1/1 Running 0 5m35s 10.244.2.12 worker2 <none> <none>
default kubia-nwjcc 1/1 Running 0 16h 10.244.1.27 worker1 <none> <none>
kube-system coredns-bccdc95cf-792px 1/1 Running 4 5d19h 10.244.0.11 master1 <none> <none>
kube-system coredns-bccdc95cf-bc76j 1/1 Running 4 5d19h 10.244.0.10 master1 <none> <none>
kube-system etcd-master1 1/1 Running 8 5d19h 192.168.56.11 master1 <none> <none>
kube-system kube-apiserver-master1 1/1 Running 7 5d19h 192.168.56.11 master1 <none> <none>
kube-system kube-controller-manager-master1 1/1 Running 7 5d18h 192.168.56.11 master1 <none> <none>
kube-system kube-flannel-ds-amd64-9trbq 1/1 Running 3 5d18h 192.168.56.21 worker1 <none> <none>
kube-system kube-flannel-ds-amd64-btt74 1/1 Running 5 5d18h 192.168.56.11 master1 <none> <none>
kube-system kube-flannel-ds-amd64-swzzd 1/1 Running 0 3d20h 192.168.56.22 worker2 <none> <none>
kube-system kube-proxy-27zfk 1/1 Running 7 5d19h 192.168.56.11 master1 <none> <none>
kube-system kube-proxy-79kt9 1/1 Running 0 3d20h 192.168.56.22 worker2 <none> <none>
kube-system kube-proxy-lx4gk 1/1 Running 3 5d18h 192.168.56.21 worker1 <none> <none>
kube-system kube-scheduler-master1 1/1 Running 7 5d19h 192.168.56.11 master1 <none> <none>
Мой ожидаемый возврат: при использовании curl
доступ svc
, svc
можетпроизвольно получить доступ к pod
на разных узлах следующим образом:
root@master1:~# kubectl get po
NAME READY STATUS RESTARTS AGE
kubia-nwjcc 1/1 Running 0 50m
kubia-zcpbb 1/1 Running 0 50m
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-nwjcc
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-zcpbb
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-zcpbb
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-nwjcc
И теперь возвращаемые результаты пяти тестов выглядят следующим образом:
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-nwjcc
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-nwjcc
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
command terminated with exit code 7
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
You've hit kubia-nwjcc
root@master1:~# k exec kubia-nwjcc -- curl -s http://10.98.41.49
command terminated with exit code 7