====== Kubectl 語法整理 ====== ===== 指定特別 kubeconf 檔方式 ===== * Exp. kubeconf 檔案存放在 /iiidevops/kube-config/config * kubectl --kubeconfig /iiidevops/kube-config/config get pod ===== 檢查 K8s Cluster 的健康狀態 ===== * 參考 - https://stackoverflow.com/questions/54882727/kubectl-using-command-to-get-cluster-status * kubectl get componentstatus結果類似以下訊息: $ kubectl get componentstatus NAME STATUS MESSAGE ERROR controller-manager Healthy ok scheduler Healthy ok etcd-0 Healthy {"health":"true"} ===== 讀取 K8s Cluster Name 的方式 ===== * 參考 - https://stackoverflow.com/questions/38242062/how-to-get-kubernetes-cluster-name-from-k8s-api * 方法1 kubectl config current-context結果: rkeuser@devops2:~$ kubectl config current-context iiidevops-k8s * 方法2 kubectl config view結果: rkeuser@devops2:~$ kubectl config view apiVersion: v1 clusters: - cluster: certificate-authority-data: DATA+OMITTED server: https://172.16.0.172:6443 name: iiidevops-k8s contexts: - context: cluster: iiidevops-k8s user: kube-admin-iiidevops-k8s name: iiidevops-k8s current-context: iiidevops-k8s kind: Config preferences: {} users: - name: kube-admin-iiidevops-k8s user: client-certificate-data: REDACTED client-key-data: REDACTED ===== 顯示 K8s 內的 POD 清單 ===== * kubectl get pod Exp. localadmin@iiidevops-73:~$ kubectl get pod NAME READY STATUS RESTARTS AGE devopsapi-dbbcf7fd4-j5nv2 1/1 Running 0 36m devopsdb-5555449b8d-rd2z9 1/1 Running 0 37m devopsui-84496c7fcc-bd99r 1/1 Running 0 126m redmine-547cbdbbbb-wk9s6 1/1 Running 1 17h redmine-postgresql-6fb9475c6c-gs9gh 1/1 Running 0 17h sonarqube-server-6ccbf4c54f-vksmp 1/1 Running 0 17h * 加上 -n 參數 指定所要查詢的 namespace 內 pod 清單 kubectl get pod -n kube-system Exp. $ kubectl get pod -n kube-system NAME READY STATUS RESTARTS AGE calico-kube-controllers-c955d588c-kcm7r 1/1 Running 2 36h calico-node-sghsm 1/1 Running 2 36h : rke-metrics-addon-deploy-job-dhjbl 0/1 Completed 0 36h rke-network-plugin-deploy-job-6vzqh 0/1 Completed 0 36h * 加上 -A 參數可呈現所有 namespace 的 pod 清單 kubectl get pod -A Exp. localadmin@iiidevops-hv-2:~$ kubectl get pod -A NAMESPACE NAME READY STATUS RESTARTS AGE cattle-pipeline registry-proxy-96bbj 1/1 Running 0 40m cattle-system cattle-cluster-agent-7d569b986c-57485 1/1 Running 0 145m : kube-system rke-metrics-addon-deploy-job-tb2sn 0/1 Completed 0 146m kube-system rke-network-plugin-deploy-job-pcgss 0/1 Completed 0 146m p-8kvwh-pipeline docker-registry-57fbddc6cc-ch9cw 1/1 Running 0 40m p-8kvwh-pipeline jenkins-f4d6b89cb-h8554 1/1 Running 0 40m p-8kvwh-pipeline minio-5ccb99b5c7-kp9lc 1/1 Running 0 40m ===== 顯示 K8s 內 POD 的 logs ===== * kubectl logs [pod NAME] Exp. localadmin@iiidevops-73:~$ kubectl logs redmine-547cbdbbbb-wk9s6 | tail -20 I, [2020-12-21T10:47:03.089762 #1] INFO -- : Rendered enumerations/_form.html.erb (2.8ms) I, [2020-12-21T10:47:03.090267 #1] INFO -- : Rendered enumerations/new.html.erb within layouts/admin (4.2ms) I, [2020-12-21T10:47:03.095432 #1] INFO -- : Rendered admin/_menu.html.erb (4.9ms) I, [2020-12-21T10:47:03.095745 #1] INFO -- : Rendering layouts/base.html.erb I, [2020-12-21T10:47:03.107140 #1] INFO -- : Rendered layouts/base.html.erb (11.3ms) I, [2020-12-21T10:47:03.107464 #1] INFO -- : Completed 200 OK in 32ms (Views: 19.9ms | ActiveRecord: 5.8ms) I, [2020-12-21T10:47:05.101236 #1] INFO -- : Started POST "/enumerations" for 10.20.0.74 at 2020-12-21 10:47:05 +0000 I, [2020-12-21T10:47:05.102407 #1] INFO -- : Processing by EnumerationsController#create as HTML I, [2020-12-21T10:47:05.102487 #1] INFO -- : Parameters: {"utf8"=>"✓", "authenticity_token"=>"wRaItdciacpkIjcxxxxxxxxxxrdQWdKf66WuZPq6AGAIQyK9BLeuyOlyKODKQedaCNdAoADOadTy+3UH4mTeg==", "enumeration"=>{"type"=>"IssuePriority", "name"=>"Low", "active"=>"1", "is_default"=>"0"}, "commit"=>"Create"} I, [2020-12-21T10:47:05.112128 #1] INFO -- : Current user: admin (id=1) I, [2020-12-21T10:47:05.192218 #1] INFO -- : Redirected to http://10.20.0.74:32748/enumerations I, [2020-12-21T10:47:05.192469 #1] INFO -- : Completed 302 Found in 90ms (ActiveRecord: 17.5ms) 10.20.0.74 - - [21/Dec/2020:10:47:05 UTC] "POST /enumerations HTTP/1.1" 302 102 http://10.20.0.74:32748/enumerations/new?type=IssuePriority -> /enumerations 10.20.0.74 - - [21/Dec/2020:10:47:05 UTC] "GET /enumerations HTTP/1.1" 200 8526 http://10.20.0.74:32748/enumerations/new?type=IssuePriority -> /enumerations 10.20.0.74 - - [22/Dec/2020:02:21:47 UTC] "GET /users/current.json HTTP/1.1" 200 253 - -> /users/current.json 10.20.0.74 - - [22/Dec/2020:02:21:47 UTC] "GET /users.json?offset=0&limit=25&key=d64c31axxxxxxxxxxd085fc5825ec257b31a3ec7 HTTP/1.1" 200 230 - -> /users.json?offset=0&limit=25&key=d64c31aff3xxxxxxxxxx5fc5825ec257b31a3ec7 ===== 顯示 K8s 內 POD 的描述資訊 ===== * kubectl describe pod [pod NAME] Exp. localadmin@iiidevops-71:~/deploy-devops$ kubectl describe pod devopsapi-cdccbcb48-qv4n9 Name: devopsapi-cdccbcb48-qv4n9 Namespace: default Priority: 0 Node: iiidevops-72/10.20.0.72 Start Time: Thu, 24 Dec 2020 06:27:37 +0000 Labels: app=devopsapi pod-template-hash=cdccbcb48 : : Normal Pulling 15s (x2 over 38s) kubelet Pulling image "iiiorg/devops-api:develop" Warning Failed 11s (x2 over 34s) kubelet Failed to pull image "iiiorg/devops-api:develop": rpc error: code = Unknown desc = Error response from daemon: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit Warning Failed 11s (x2 over 34s) kubelet Error: ErrImagePull ===== 進入一個 POD 內操作 ===== * kubectl exec -it [POD Name] -- bash Exp. localadmin@iiidevops-hv-2:~$ kubectl exec -it devopsapi-74c78bb4c8-77phj -- bash root@devopsapi-74c78bb4c8-77phj:/usr/src/app# ls -lt total 76 drwxr-xr-x 1 root root 4096 Jan 23 08:18 apis drwxrwxrwx 2 root root 4096 Jan 23 08:18 logs -rw-r--r-- 1 root root 41 Jan 22 22:15 git_commit -rwxr-xr-x 1 root root 435 Jan 22 22:15 Dockerfile -rwxr-xr-x 1 root root 11357 Jan 22 22:15 LICENSE -rwxr-xr-x 1 root root 878 Jan 22 22:15 README.md -rwxr-xr-x 1 root root 1994 Jan 22 22:15 _alembic.ini : : -rwxr-xr-x 1 root root 3133 Jan 22 22:15 k8s_config root@devopsapi-c9ddc8cdf-mrb9f:/usr/src/app# * 如果要進入不同 namespace 的 pod 操作就需要加上 --namespace="xxx" 的參數 Exp. localadmin@iiidevops-hv-2:~$ kubectl exec -it --namespace="p-8kvwh-pipeline" minio-5ccb99b5c7-kp9lc -- traceroute 172.17.13.183 traceroute to 172.17.13.183 (172.17.13.183), 30 hops max, 46 byte packets 1 172-17-13-183.kubernetes.default.svc.cluster.local (172.17.13.183) 0.007 ms 0.009 ms 0.007 ms ===== 顯示 K8s 內的 deploy 清單 ===== * kubctl get deploy Exp. localadmin@iiidevops-73:~$ kubectl get deploy NAME READY UP-TO-DATE AVAILABLE AGE devopsapi 1/1 1 1 17h devopsdb 1/1 1 1 37m devopsui 1/1 1 1 17h redmine 1/1 1 1 17h redmine-postgresql 1/1 1 1 17h sonarqube-server 1/1 1 1 17h ===== 移除 K8s 內的 deploy pod ===== * kubctl delete deploy [deploy NAME] Exp. localadmin@iiidevops-73:~$ kubectl delete deploy devopsui devopsdb devopsapi deployment.apps "devopsui" deleted deployment.apps "devopsdb" deleted deployment.apps "devopsapi" deleted ===== 顯示 K8s 內的 namespace 清單 ===== * kubctl get namespace Exp. iiidevops@iiidevops1:~$ kubectl get namespace NAME STATUS AGE account Active 49d cattle-pipeline Active 6d22h cattle-system Active 50d default Active 50d iii-devops-toolchain Active 6d22h ingress-nginx Active 50d kube-node-lease Active 50d kube-public Active 50d kube-system Active 50d p-pdx2d-pipeline Active 6d22h security-scan Active 50d ===== 移除 K8s 內的 namespace deploy pod ===== * kubctl delete namespace [namespace NAME] Exp. iiidevops@iiidevops1:~$ kubectl delete namespace iii-devops-toolchain namespace "iii-devops-toolchain" deleted ===== 讀取 Secret 的內容 ===== * kubectl get secret [secret_name] Exp. rkeuser@dev4-86:~$ kubectl get secret NAME TYPE DATA AGE default-token-pssx6 kubernetes.io/service-account-token 3 21d gitlab Opaque 1 21d harbor Opaque 1 21d harbor-harbor-clair Opaque 3 21d harbor-harbor-clair-internal-tls kubernetes.io/tls 3 21d harbor-harbor-core Opaque 8 21d : * 顯示 secret 的內容, 有定義那些 keykubectl describe secret [secret_name] Exp. rkeuser@dev4-86:~$ kubectl describe secret harbor Name: harbor Namespace: default Labels: Annotations: field.cattle.io/creatorId: user-jwvbx field.cattle.io/projectId: local:p-rhflt lifecycle.cattle.io/create.secretsController_local: true secret.user.cattle.io/secret: true Type: Opaque Data ==== harbor-local: 25 bytes * 顯示 secret key 的 value 編碼內容 kubectl get secrets/ --template={{.data.}} Exp. kubectl get secrets/harbor --template={{.data.harbor-local}} ** 如果要直接解碼可使用 base64 -d 的方式處理** Exp. kubectl get secrets/harbor --template={{.data.harbor-local}} | base64 -d ===== 讀取 kubelet 內的 pod 目錄編號 ===== * 實際 pod 的檔案存在 node 內的 /var/lib/kubelet/pods 內, 可透過以下語法獲知 pod 的目錄編號 kubectl get pods -A -o custom-columns=NodeName:.spec.nodeName,PodName:.metadata.name,PodUID:.metadata.uid * ++看實際範例| rkeuser@demo-77:~$ kubectl get pods -A -o custom-columns=NodeName:.spec.nodeName,PodName:.metadata.name,PodUID:.metadata.uid NodeName PodName PodUID 10.20.0.79 a1-master-db-dpy-79bc97bf96-xmqxw 34dad11c-7f38-44c1-b1b0-e06d760d2a7e 10.20.0.79 a1-master-db-gui-7cc89bcb59-vlhtz 9cc444c9-3986-4ba2-a535-9f44f6bb10cf 10.20.0.79 a1-master-sq-4-wkv2l 94dc6771-bea0-46bd-a0ec-0128e7c5c16d 10.20.0.78 apeg-python-flask-master-serv-dpy-86b655666-9ngdf 0903dcd1-c1f5-4704-b8ba-7991d11e882d 10.20.0.78 aptgit-220209-master-db-dpy-5f7986d9c-wvv2c 7209d08f-d0b8-428d-922c-87b3f6fe5787 10.20.0.77 aptgit-220209-master-db-gui-67bbbf77cb-h9qxh 498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7 10.20.0.79 aptgit-220209-master-db-gui-67bbbf77cb-t79qf ba6e310c-a106-426e-910a-290e836c40a9 10.20.0.78 aptgit-220209-master-serv-dpy-5cf7cccd4d-66vns 522553e2-3323-44cb-bb02-3995d625c033 10.20.0.77 aptgit-220209-master-serv-dpy-5cf7cccd4d-k2jl8 f8a147db-3eee-4d40-b051-f6b00bc0a644 : 直接看 aptgit-220209-master-db-gui-67bbbf77cb-h9qxh -> 498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7 這個 POD 的檔案 rkeuser@demo-77:~$ sudo ls -lRt /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7 /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7: total 16 -rw-r--r-- 1 root root 241 Jan 7 09:04 etc-hosts drwxr-x--- 3 root root 4096 Jun 25 2022 containers drwxr-x--- 3 root root 4096 Jun 25 2022 plugins drwxr-x--- 3 root root 4096 Jun 25 2022 volumes /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/containers: total 4 drwxr-x--- 2 root root 4096 Jan 7 09:04 mariadb-gui /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/containers/mariadb-gui: total 0 -rw-rw-rw- 1 root root 0 Jan 7 09:04 832a851d -rw-rw-rw- 1 root root 0 Nov 19 09:26 d65ebd13 -rw-rw-rw- 1 root root 0 Oct 15 06:39 d516d827 -rw-rw-rw- 1 root root 0 Oct 14 19:16 ea72f4fc -rw-rw-rw- 1 root root 0 Sep 17 11:11 94285167 -rw-rw-rw- 1 root root 0 Aug 28 18:14 edc19f39 -rw-rw-rw- 1 root root 0 Jul 30 2022 cbf94e15 -rw-rw-rw- 1 root root 0 Jul 14 2022 f3f9f859 -rw-rw-rw- 1 root root 0 Jun 25 2022 46143b63 /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/plugins: total 4 drwxr-x--- 2 root root 4096 Jan 30 07:48 kubernetes.io~empty-dir /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/plugins/kubernetes.io~empty-dir: total 0 /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/volumes: total 4 drwxr-xr-x 2 root root 4096 Jan 30 07:48 kubernetes.io~secret /var/lib/kubelet/pods/498451f9-fa3a-4fa6-bd2c-dd1ae1d9a3b7/volumes/kubernetes.io~secret: total 0 rkeuser@demo-77:~$ ++ {{tag>k8s iiidevops kubectl}}