====== 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}}