如何查看k8s存在etcd中的数据(转)

原文 https://yq.aliyun.com/articles/561888

一直有这个冲动，

想知道kubernetes往etcd里放了哪些数据，是如何组织的。

能看到，才有把握知道它的实现和细节。

找了很多文档，终于找到靠谱的。

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https://www.jianshu.com/p/f9f83dd21770

===========================

 

我是使用kubeadm工具安装的集群，要解除集群的资源占用要先把一些容器停掉，把kube-apiserver的编排文件从/etc/kubernetes/manifests/目录下先移出来，kubelet检查到会停止相应的pods,没有了kube-apiserver集群不会再创建新的pods,这时kubectl不可用了，使用docker命令把spinnaker项目的容器都删掉系统资源就能空闲出来。这时etcd还是正常的，用docker工具直接进入etcd。
操作etcd有命令行工具etcdctl，有两个api版本互不兼容的，系统默认的v2版本，kubernetes集群使用的是v3版本，v2版本下是看不到v3版本的数据的，我也是找了些资料才了解这个情况。
使用环境变量定义api版本
export ETCDCTL_API=3
etcd有目录结构类似linux文件系统，获取所有key看一看：
etcdctl get / --prefix --keys-only

一看就可以大概理解kubenetes的数据结构了，查询命名空间下所有部署的数据：
etcdctl get /registry/deployments/default --prefix --keys-only

把想删除的删掉，列如：
etcdctl del /registry/deployments/default/elevated-dragonfly-spinn-front50
删除deployments，pods这可以了，稍微减少一些资源，让kube-apiserver可以正常工作即可，其它资源还可以使用kubectl工具删除
删掉些资源后退出etcd把kube-apiserver的编排文件放回/etc/kubernetes/manifests目录，服务会再次启动，然后再清理重新部署。

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k8s 1.9.3放在etcd里的根数据结构如下：

 

etcdctl get / --prefix --keys-only

/registry/apiregistration.k8s.io/apiservices/v1.

/registry/apiregistration.k8s.io/apiservices/v1.apps

/registry/apiregistration.k8s.io/apiservices/v1.authentication.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1.authorization.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1.autoscaling

/registry/apiregistration.k8s.io/apiservices/v1.batch

/registry/apiregistration.k8s.io/apiservices/v1.networking.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1.rbac.authorization.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1.storage.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.admissionregistration.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.apiextensions.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.apps

/registry/apiregistration.k8s.io/apiservices/v1beta1.authentication.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.authorization.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.batch

/registry/apiregistration.k8s.io/apiservices/v1beta1.certificates.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.events.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.extensions

/registry/apiregistration.k8s.io/apiservices/v1beta1.policy

/registry/apiregistration.k8s.io/apiservices/v1beta1.rbac.authorization.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta1.storage.k8s.io

/registry/apiregistration.k8s.io/apiservices/v1beta2.apps

/registry/apiregistration.k8s.io/apiservices/v2beta1.autoscaling

/registry/certificatesigningrequests/node-csr-NMpLG7rhBYiuAyRD739h79x2qhbhWn-UtLPFwJWJU1Y

/registry/certificatesigningrequests/node-csr-v96LRHUfeRD3iAZgHdUYxDaT1kkHvIilDnLZy2GPSew

/registry/clusterrolebindings/cluster-admin

/registry/clusterrolebindings/flannel

/registry/clusterrolebindings/heapster

/registry/clusterrolebindings/kubeadm:kubelet-bootstrap

/registry/clusterrolebindings/kubeadm:node-autoapprove-bootstrap

/registry/clusterrolebindings/kubeadm:node-autoapprove-certificate-rotation

/registry/clusterrolebindings/kubeadm:node-proxier

/registry/clusterrolebindings/kubernetes-dashboard

/registry/clusterrolebindings/system:aws-cloud-provider

/registry/clusterrolebindings/system:basic-user

/registry/clusterrolebindings/system:controller:attachdetach-controller

/registry/clusterrolebindings/system:controller:certificate-controller

/registry/clusterrolebindings/system:controller:clusterrole-aggregation-controller

/registry/clusterrolebindings/system:controller:cronjob-controller

/registry/clusterrolebindings/system:controller:daemon-set-controller

/registry/clusterrolebindings/system:controller:deployment-controller

/registry/clusterrolebindings/system:controller:disruption-controller

/registry/clusterrolebindings/system:controller:endpoint-controller

/registry/clusterrolebindings/system:controller:generic-garbage-collector

/registry/clusterrolebindings/system:controller:horizontal-pod-autoscaler

/registry/clusterrolebindings/system:controller:job-controller

/registry/clusterrolebindings/system:controller:namespace-controller

/registry/clusterrolebindings/system:controller:node-controller

/registry/clusterrolebindings/system:controller:persistent-volume-binder

/registry/clusterrolebindings/system:controller:pod-garbage-collector

/registry/clusterrolebindings/system:controller:replicaset-controller

/registry/clusterrolebindings/system:controller:replication-controller

/registry/clusterrolebindings/system:controller:resourcequota-controller

/registry/clusterrolebindings/system:controller:route-controller

/registry/clusterrolebindings/system:controller:service-account-controller

/registry/clusterrolebindings/system:controller:service-controller

/registry/clusterrolebindings/system:controller:statefulset-controller

/registry/clusterrolebindings/system:controller:ttl-controller

/registry/clusterrolebindings/system:coredns

/registry/clusterrolebindings/system:discovery

/registry/clusterrolebindings/system:kube-controller-manager

/registry/clusterrolebindings/system:kube-dns

/registry/clusterrolebindings/system:kube-scheduler

/registry/clusterrolebindings/system:node

/registry/clusterrolebindings/system:node-proxier

/registry/clusterroles/admin

/registry/clusterroles/cluster-admin

/registry/clusterroles/edit

/registry/clusterroles/flannel

/registry/clusterroles/system:aggregate-to-admin

/registry/clusterroles/system:aggregate-to-edit

/registry/clusterroles/system:aggregate-to-view

/registry/clusterroles/system:auth-delegator

/registry/clusterroles/system:aws-cloud-provider

/registry/clusterroles/system:basic-user

/registry/clusterroles/system:certificates.k8s.io:certificatesigningrequests:nodeclient

/registry/clusterroles/system:certificates.k8s.io:certificatesigningrequests:selfnodeclient

/registry/clusterroles/system:controller:attachdetach-controller

/registry/clusterroles/system:controller:certificate-controller

/registry/clusterroles/system:controller:clusterrole-aggregation-controller

/registry/clusterroles/system:controller:cronjob-controller

/registry/clusterroles/system:controller:daemon-set-controller

/registry/clusterroles/system:controller:deployment-controller

/registry/clusterroles/system:controller:disruption-controller

/registry/clusterroles/system:controller:endpoint-controller

/registry/clusterroles/system:controller:generic-garbage-collector

/registry/clusterroles/system:controller:horizontal-pod-autoscaler

/registry/clusterroles/system:controller:job-controller

/registry/clusterroles/system:controller:namespace-controller

/registry/clusterroles/system:controller:node-controller

/registry/clusterroles/system:controller:persistent-volume-binder

/registry/clusterroles/system:controller:pod-garbage-collector

/registry/clusterroles/system:controller:replicaset-controller

/registry/clusterroles/system:controller:replication-controller

/registry/clusterroles/system:controller:resourcequota-controller

/registry/clusterroles/system:controller:route-controller

/registry/clusterroles/system:controller:service-account-controller

/registry/clusterroles/system:controller:service-controller

/registry/clusterroles/system:controller:statefulset-controller

/registry/clusterroles/system:controller:ttl-controller

/registry/clusterroles/system:coredns

/registry/clusterroles/system:discovery

/registry/clusterroles/system:heapster

/registry/clusterroles/system:kube-aggregator

/registry/clusterroles/system:kube-controller-manager

/registry/clusterroles/system:kube-dns

/registry/clusterroles/system:kube-scheduler

/registry/clusterroles/system:node

/registry/clusterroles/system:node-bootstrapper

/registry/clusterroles/system:node-problem-detector

/registry/clusterroles/system:node-proxier

/registry/clusterroles/system:persistent-volume-provisioner

/registry/clusterroles/view

/registry/configmaps/kube-public/cluster-info

/registry/configmaps/kube-system/coredns

/registry/configmaps/kube-system/extension-apiserver-authentication

/registry/configmaps/kube-system/kube-flannel-cfg

/registry/configmaps/kube-system/kube-proxy

/registry/configmaps/kube-system/kubeadm-config

/registry/configmaps/kube-system/kubernetes-dashboard-settings

/registry/controllerrevisions/kube-system/kube-flannel-ds-dd8484577

/registry/controllerrevisions/kube-system/kube-proxy-95cfb667c

/registry/cronjobs/default/hello

/registry/daemonsets/kube-system/kube-flannel-ds

/registry/daemonsets/kube-system/kube-proxy

/registry/deployments/default/flower

/registry/deployments/default/pc-saveapi

/registry/deployments/default/pxxxm-django

/registry/deployments/default/pxxxm-redis

/registry/deployments/default/pxxxm-tengine-proxy

/registry/deployments/default/pxxxm-tengine-static

/registry/deployments/default/pxxxmlogapi-nj

/registry/deployments/kube-system/coredns

/registry/deployments/kube-system/heapster

/registry/deployments/kube-system/kubernetes-dashboard

/registry/deployments/kube-system/monitoring-grafana

/registry/deployments/kube-system/monitoring-influxdb

/registry/events/default/flower-554b58b968-n48sj.151de36ccc190d41

/registry/events/default/flower-554b58b968-n48sj.151de36e0d128ca9

/registry/events/default/hello.151e1bcd521ee391

/registry/jobs/default/hello-1521622920

/registry/jobs/default/hello-1521622980

/registry/jobs/default/hello-1521623040

/registry/minions/cnsz131381

/registry/minions/cnsz131382

/registry/minions/cnsz131383

/registry/namespaces/default

/registry/namespaces/kube-public

/registry/namespaces/kube-system

/registry/pods/default/flower-554b58b968-n48sj

/registry/pods/default/hello-1521622920-5z4bl

/registry/pods/default/hello-1521622980-4qcrd

/registry/pods/default/hello-1521623040-szf4f

/registry/pods/default/pc-saveapi-58cf87b4f5-5x2d8

/registry/pods/default/pxxxm-django-8466f46d84-4mjtf

/registry/pods/default/pxxxm-django-8466f46d84-pnqzp

/registry/pods/default/pxxxm-django-8466f46d84-x5d8z

/registry/pods/default/pxxxm-redis-767c5d5966-l88qj

/registry/pods/default/pxxxm-tengine-proxy-75d874d898-8275h

/registry/pods/default/pxxxm-tengine-static-7d7bb5d5b6-7568z

/registry/pods/default/pxxxmlogapi-nj-687cc89b96-ps4np

/registry/pods/kube-system/coredns-65dcdb4cf-hgmdv

/registry/pods/kube-system/etcd-cnsz131383

/registry/pods/kube-system/heapster-5996df699d-d8798

/registry/pods/kube-system/kube-apiserver-cnsz131383

/registry/pods/kube-system/kube-controller-manager-cnsz131383

/registry/pods/kube-system/kube-flannel-ds-gr8jp

/registry/pods/kube-system/kube-flannel-ds-p4tpq

/registry/pods/kube-system/kube-flannel-ds-z7s96

/registry/pods/kube-system/kube-proxy-cgjhk

/registry/pods/kube-system/kube-proxy-f7snz

/registry/pods/kube-system/kube-proxy-l98gl

/registry/pods/kube-system/kube-scheduler-cnsz131383

/registry/pods/kube-system/kubernetes-dashboard-5bd6f767c7-vr6sg

/registry/pods/kube-system/monitoring-grafana-6bf544559d-cd6d4

/registry/pods/kube-system/monitoring-influxdb-865d95895b-n9sls

/registry/ranges/serviceips

/registry/ranges/servicenodeports

/registry/replicasets/default/flower-554b58b968

/registry/replicasets/default/pc-saveapi-58cf87b4f5

/registry/replicasets/default/pxxxm-django-8466f46d84

/registry/replicasets/default/pxxxm-redis-767c5d5966

/registry/replicasets/default/pxxxm-tengine-proxy-75d874d898

/registry/replicasets/default/pxxxm-tengine-static-7d7bb5d5b6

/registry/replicasets/default/pxxxmlogapi-nj-687cc89b96

/registry/replicasets/kube-system/coredns-65dcdb4cf

/registry/replicasets/kube-system/heapster-5996df699d

/registry/replicasets/kube-system/kubernetes-dashboard-5bd6f767c7

/registry/replicasets/kube-system/monitoring-grafana-6bf544559d

/registry/replicasets/kube-system/monitoring-influxdb-865d95895b

/registry/rolebindings/kube-public/kubeadm:bootstrap-signer-clusterinfo

/registry/rolebindings/kube-public/system:controller:bootstrap-signer

/registry/rolebindings/kube-system/kubernetes-dashboard-minimal

/registry/rolebindings/kube-system/system::leader-locking-kube-controller-manager

/registry/rolebindings/kube-system/system::leader-locking-kube-scheduler

/registry/rolebindings/kube-system/system:controller:bootstrap-signer

/registry/rolebindings/kube-system/system:controller:cloud-provider

/registry/rolebindings/kube-system/system:controller:token-cleaner

/registry/roles/kube-public/kubeadm:bootstrap-signer-clusterinfo

/registry/roles/kube-public/system:controller:bootstrap-signer

/registry/roles/kube-system/extension-apiserver-authentication-reader

/registry/roles/kube-system/kubernetes-dashboard-minimal

/registry/roles/kube-system/system::leader-locking-kube-controller-manager

/registry/roles/kube-system/system::leader-locking-kube-scheduler

/registry/roles/kube-system/system:controller:bootstrap-signer

/registry/roles/kube-system/system:controller:cloud-provider

/registry/roles/kube-system/system:controller:token-cleaner

/registry/secrets/default/default-token-hfj82

/registry/secrets/kube-public/default-token-wpbfs

/registry/secrets/kube-system/attachdetach-controller-token-7jsks

/registry/secrets/kube-system/bootstrap-signer-token-xs87g

/registry/secrets/kube-system/certificate-controller-token-x4swr

/registry/secrets/kube-system/clusterrole-aggregation-controller-token-z7w85

/registry/secrets/kube-system/coredns-token-tbbbw

/registry/secrets/kube-system/cronjob-controller-token-p44bn

/registry/secrets/kube-system/daemon-set-controller-token-4klc2

/registry/secrets/kube-system/default-token-g9lcp

/registry/secrets/kube-system/deployment-controller-token-gfcdt

/registry/secrets/kube-system/disruption-controller-token-vs4dz

/registry/secrets/kube-system/endpoint-controller-token-92kn2

/registry/secrets/kube-system/flannel-token-wvgjq

/registry/secrets/kube-system/generic-garbage-collector-token-pcpnq

/registry/secrets/kube-system/heapster-token-6szhz

/registry/secrets/kube-system/horizontal-pod-autoscaler-token-xqcl5

/registry/secrets/kube-system/job-controller-token-422zr

/registry/secrets/kube-system/kube-proxy-token-k5rfq

/registry/secrets/kube-system/kubernetes-dashboard-certs

/registry/secrets/kube-system/kubernetes-dashboard-key-holder

/registry/secrets/kube-system/kubernetes-dashboard-token-kpkw7

/registry/secrets/kube-system/namespace-controller-token-r57ss

/registry/secrets/kube-system/node-controller-token-5f7sm

/registry/secrets/kube-system/persistent-volume-binder-token-7rnt2

/registry/secrets/kube-system/pod-garbage-collector-token-2txwf

/registry/secrets/kube-system/replicaset-controller-token-zh9xq

/registry/secrets/kube-system/replication-controller-token-q69jz

/registry/secrets/kube-system/resourcequota-controller-token-92hn4

/registry/secrets/kube-system/service-account-controller-token-vvw5d

/registry/secrets/kube-system/service-controller-token-lslnf

/registry/secrets/kube-system/statefulset-controller-token-wdqjt

/registry/secrets/kube-system/token-cleaner-token-9zzpv

/registry/secrets/kube-system/ttl-controller-token-tc7pl

/registry/serviceaccounts/default/default

/registry/serviceaccounts/kube-public/default

/registry/serviceaccounts/kube-system/attachdetach-controller

/registry/serviceaccounts/kube-system/bootstrap-signer

/registry/serviceaccounts/kube-system/certificate-controller

/registry/serviceaccounts/kube-system/clusterrole-aggregation-controller

/registry/serviceaccounts/kube-system/coredns

/registry/serviceaccounts/kube-system/cronjob-controller

/registry/serviceaccounts/kube-system/daemon-set-controller

/registry/serviceaccounts/kube-system/default

/registry/serviceaccounts/kube-system/deployment-controller

/registry/serviceaccounts/kube-system/disruption-controller

/registry/serviceaccounts/kube-system/endpoint-controller

/registry/serviceaccounts/kube-system/flannel

/registry/serviceaccounts/kube-system/generic-garbage-collector

/registry/serviceaccounts/kube-system/heapster

/registry/serviceaccounts/kube-system/horizontal-pod-autoscaler

/registry/serviceaccounts/kube-system/job-controller

/registry/serviceaccounts/kube-system/kube-proxy

/registry/serviceaccounts/kube-system/kubernetes-dashboard

/registry/serviceaccounts/kube-system/namespace-controller

/registry/serviceaccounts/kube-system/node-controller

/registry/serviceaccounts/kube-system/persistent-volume-binder

/registry/serviceaccounts/kube-system/pod-garbage-collector

/registry/serviceaccounts/kube-system/replicaset-controller

/registry/serviceaccounts/kube-system/replication-controller

/registry/serviceaccounts/kube-system/resourcequota-controller

/registry/serviceaccounts/kube-system/service-account-controller

/registry/serviceaccounts/kube-system/service-controller

/registry/serviceaccounts/kube-system/statefulset-controller

/registry/serviceaccounts/kube-system/token-cleaner

/registry/serviceaccounts/kube-system/ttl-controller

/registry/services/endpoints/default/flower

/registry/services/endpoints/default/kubernetes

/registry/services/endpoints/default/pc-saveapi

/registry/services/endpoints/default/pxxxm-django

/registry/services/endpoints/default/pxxxm-redis

/registry/services/endpoints/default/pxxxm-tengine-proxy

/registry/services/endpoints/default/pxxxm-tengine-static

/registry/services/endpoints/default/pxxxmlogapi-nj

/registry/services/endpoints/kube-system/heapster

/registry/services/endpoints/kube-system/kube-controller-manager

/registry/services/endpoints/kube-system/kube-dns

/registry/services/endpoints/kube-system/kube-scheduler

/registry/services/endpoints/kube-system/kubernetes-dashboard

/registry/services/endpoints/kube-system/monitoring-grafana

/registry/services/endpoints/kube-system/monitoring-influxdb

/registry/services/specs/default/flower

/registry/services/specs/default/kubernetes

/registry/services/specs/default/pc-saveapi

/registry/services/specs/default/pxxxm-django

/registry/services/specs/default/pxxxm-redis

/registry/services/specs/default/pxxxm-tengine-proxy

/registry/services/specs/default/pxxxm-tengine-static

/registry/services/specs/default/pxxxmlogapi-nj

/registry/services/specs/kube-system/heapster

/registry/services/specs/kube-system/kube-dns

/registry/services/specs/kube-system/kubernetes-dashboard

/registry/services/specs/kube-system/monitoring-grafana

/registry/services/specs/kube-system/monitoring-influxdb