kubernetes之kubectl与YAML详解1
- 2022 年 11 月 7 日
- 筆記
- 云计算docker/k8s/openstack
k8s集群的日志，带有组件的信息，多看日志。
kubectl命令汇总
kubectl命令汇总
kubectl命令帮助信息
[root@mcwk8s04 ~]# kubectl -h kubectl controls the Kubernetes cluster manager. Find more information at: https://kubernetes.io/docs/reference/kubectl/overview/ Basic Commands (Beginner): create Create a resource from a file or from stdin. expose Take a replication controller, service, deployment or pod and expose it as a new Kubernetes Service run Run a particular image on the cluster set Set specific features on objects Basic Commands (Intermediate): explain Documentation of resources get Display one or many resources edit Edit a resource on the server delete Delete resources by filenames, stdin, resources and names, or by resources and label selector Deploy Commands: rollout Manage the rollout of a resource scale Set a new size for a Deployment, ReplicaSet, Replication Controller, or Job autoscale Auto-scale a Deployment, ReplicaSet, or ReplicationController Cluster Management Commands: certificate Modify certificate resources. cluster-info Display cluster info top Display Resource (CPU/Memory/Storage) usage. cordon Mark node as unschedulable uncordon Mark node as schedulable drain Drain node in preparation for maintenance taint Update the taints on one or more nodes Troubleshooting and Debugging Commands: describe Show details of a specific resource or group of resources logs Print the logs for a container in a pod attach Attach to a running container exec Execute a command in a container port-forward Forward one or more local ports to a pod proxy Run a proxy to the Kubernetes API server cp Copy files and directories to and from containers. auth Inspect authorization Advanced Commands: diff Diff live version against would-be applied version apply Apply a configuration to a resource by filename or stdin patch Update field(s) of a resource using strategic merge patch replace Replace a resource by filename or stdin wait Experimental: Wait for a specific condition on one or many resources. convert Convert config files between different API versions kustomize Build a kustomization target from a directory or a remote url. Settings Commands: label Update the labels on a resource annotate Update the annotations on a resource completion Output shell completion code for the specified shell (bash or zsh) Other Commands: api-resources Print the supported API resources on the server api-versions Print the supported API versions on the server, in the form of "group/version" config Modify kubeconfig files plugin Provides utilities for interacting with plugins. version Print the client and server version information Usage: kubectl [flags] [options] Use "kubectl <command> --help" for more information about a given command. Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s04 ~]#
kubectl run 命令帮助信息
[root@mcwk8s04 ~]# kubectl run --help Create and run a particular image, possibly replicated. Creates a deployment or job to manage the created container(s). Examples: # Start a single instance of nginx. kubectl run nginx --image=nginx # Start a single instance of hazelcast and let the container expose port 5701 . kubectl run hazelcast --image=hazelcast --port=5701 # Start a single instance of hazelcast and set environment variables "DNS_DOMAIN=cluster" and "POD_NAMESPACE=default" in the container. kubectl run hazelcast --image=hazelcast --env="DNS_DOMAIN=cluster" --env="POD_NAMESPACE=default" # Start a single instance of hazelcast and set labels "app=hazelcast" and "env=prod" in the container. kubectl run hazelcast --image=hazelcast --labels="app=hazelcast,env=prod" # Start a replicated instance of nginx. kubectl run nginx --image=nginx --replicas=5 # Dry run. Print the corresponding API objects without creating them. kubectl run nginx --image=nginx --dry-run # Start a single instance of nginx, but overload the spec of the deployment with a partial set of values parsed from JSON. kubectl run nginx --image=nginx --overrides='{ "apiVersion": "v1", "spec": { ... } }' # Start a pod of busybox and keep it in the foreground, don't restart it if it exits. kubectl run -i -t busybox --image=busybox --restart=Never # Start the nginx container using the default command, but use custom arguments (arg1 .. argN) for that command. kubectl run nginx --image=nginx -- <arg1> <arg2> ... <argN> # Start the nginx container using a different command and custom arguments. kubectl run nginx --image=nginx --command -- <cmd> <arg1> ... <argN> # Start the perl container to compute π to 2000 places and print it out. kubectl run pi --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print bpi(2000)' # Start the cron job to compute π to 2000 places and print it out every 5 minutes. kubectl run pi --schedule="0/5 * * * ?" --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print bpi(2000)' Options: --allow-missing-template-keys=true: If true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats. --attach=false: If true, wait for the Pod to start running, and then attach to the Pod as if 'kubectl attach ...' were called. Default false, unless '-i/--stdin' is set, in which case the default is true. With '--restart=Never' the exit code of the container process is returned. --cascade=true: If true, cascade the deletion of the resources managed by this resource (e.g. Pods created by a ReplicationController). Default true. --command=false: If true and extra arguments are present, use them as the 'command' field in the container, rather than the 'args' field which is the default. --dry-run=false: If true, only print the object that would be sent, without sending it. --env=[]: Environment variables to set in the container --expose=false: If true, a public, external service is created for the container(s) which are run -f, --filename=[]: to use to replace the resource. --force=false: Only used when grace-period=0. If true, immediately remove resources from API and bypass graceful deletion. Note that immediate deletion of some resources may result in inconsistency or data loss and requires confirmation. --generator='': The name of the API generator to use, see http://kubernetes.io/docs/user-guide/kubectl-conventions/#generators for a list. --grace-period=-1: Period of time in seconds given to the resource to terminate gracefully. Ignored if negative. Set to 1 for immediate shutdown. Can only be set to 0 when --force is true (force deletion). --hostport=-1: The host port mapping for the container port. To demonstrate a single-machine container. --image='': The image for the container to run. --image-pull-policy='': The image pull policy for the container. If left empty, this value will not be specified by the client and defaulted by the server -k, --kustomize='': Process a kustomization directory. This flag can't be used together with -f or -R. -l, --labels='': Comma separated labels to apply to the pod(s). Will override previous values. --leave-stdin-open=false: If the pod is started in interactive mode or with stdin, leave stdin open after the first attach completes. By default, stdin will be closed after the first attach completes. --limits='': The resource requirement limits for this container. For example, 'cpu=200m,memory=512Mi'. Note that server side components may assign limits depending on the server configuration, such as limit ranges. -o, --output='': Output format. One of: json|yaml|name|go-template|go-template-file|template|templatefile|jsonpath|jsonpath-file. --overrides='': An inline JSON override for the generated object. If this is non-empty, it is used to override the generated object. Requires that the object supply a valid apiVersion field. --pod-running-timeout=1m0s: The length of time (like 5s, 2m, or 3h, higher than zero) to wait until at least one pod is running --port='': The port that this container exposes. If --expose is true, this is also the port used by the service that is created. --quiet=false: If true, suppress prompt messages. --record=false: Record current kubectl command in the resource annotation. If set to false, do not record the command. If set to true, record the command. If not set, default to updating the existing annotation value only if one already exists. -R, --recursive=false: Process the directory used in -f, --filename recursively. Useful when you want to manage related manifests organized within the same directory. -r, --replicas=1: Number of replicas to create for this container. Default is 1. --requests='': The resource requirement requests for this container. For example, 'cpu=100m,memory=256Mi'. Note that server side components may assign requests depending on the server configuration, such as limit ranges. --restart='Always': The restart policy for this Pod. Legal values [Always, OnFailure, Never]. If set to 'Always' a deployment is created, if set to 'OnFailure' a job is created, if set to 'Never', a regular pod is created. For the latter two --replicas must be 1. Default 'Always', for CronJobs `Never`. --rm=false: If true, delete resources created in this command for attached containers. --save-config=false: If true, the configuration of current object will be saved in its annotation. Otherwise, the annotation will be unchanged. This flag is useful when you want to perform kubectl apply on this object in the future. --schedule='': A schedule in the Cron format the job should be run with. --service-generator='service/v2': The name of the generator to use for creating a service. Only used if --expose is true --service-overrides='': An inline JSON override for the generated service object. If this is non-empty, it is used to override the generated object. Requires that the object supply a valid apiVersion field. Only used if --expose is true. --serviceaccount='': Service account to set in the pod spec -i, --stdin=false: Keep stdin open on the container(s) in the pod, even if nothing is attached. --template='': Template string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview]. --timeout=0s: The length of time to wait before giving up on a delete, zero means determine a timeout from the size of the object -t, --tty=false: Allocated a TTY for each container in the pod. --wait=false: If true, wait for resources to be gone before returning. This waits for finalizers. Usage: kubectl run NAME --image=image [--env="key=value"] [--port=port] [--replicas=replicas] [--dry-run=bool] [--overrides=inline-json] [--command] -- [COMMAND] [args...] [options] Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s04 ~]#
kubectl expose帮助信息
[root@mcwk8s04 ~]# kubectl expose -h Expose a resource as a new Kubernetes service. Looks up a deployment, service, replica set, replication controller or pod by name and uses the selector for that resource as the selector for a new service on the specified port. A deployment or replica set will be exposed as a service only if its selector is convertible to a selector that service supports, i.e. when the selector contains only the matchLabels component. Note that if no port is specified via --port and the exposed resource has multiple ports, all will be re-used by the new service. Also if no labels are specified, the new service will re-use the labels from the resource it exposes. Possible resources include (case insensitive): pod (po), service (svc), replicationcontroller (rc), deployment (deploy), replicaset (rs) Examples: # Create a service for a replicated nginx, which serves on port 80 and connects to the containers on port 8000. kubectl expose rc nginx --port=80 --target-port=8000 # Create a service for a replication controller identified by type and name specified in "nginx-controller.yaml", which serves on port 80 and connects to the containers on port 8000. kubectl expose -f nginx-controller.yaml --port=80 --target-port=8000 # Create a service for a pod valid-pod, which serves on port 444 with the name "frontend" kubectl expose pod valid-pod --port=444 --name=frontend # Create a second service based on the above service, exposing the container port 8443 as port 443 with the name "nginx-https" kubectl expose service nginx --port=443 --target-port=8443 --name=nginx-https # Create a service for a replicated streaming application on port 4100 balancing UDP traffic and named 'video-stream'. kubectl expose rc streamer --port=4100 --protocol=UDP --name=video-stream # Create a service for a replicated nginx using replica set, which serves on port 80 and connects to the containers on port 8000. kubectl expose rs nginx --port=80 --target-port=8000 # Create a service for an nginx deployment, which serves on port 80 and connects to the containers on port 8000. kubectl expose deployment nginx --port=80 --target-port=8000 Options: --allow-missing-template-keys=true: If true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats. --cluster-ip='': ClusterIP to be assigned to the service. Leave empty to auto-allocate, or set to 'None' to create a headless service. --dry-run=false: If true, only print the object that would be sent, without sending it. --external-ip='': Additional external IP address (not managed by Kubernetes) to accept for the service. If this IP is routed to a node, the service can be accessed by this IP in addition to its generated service IP. -f, --filename=[]: Filename, directory, or URL to files identifying the resource to expose a service --generator='service/v2': The name of the API generator to use. There are 2 generators: 'service/v1' and 'service/v2'. The only difference between them is that service port in v1 is named 'default', while it is left unnamed in v2. Default is 'service/v2'. -k, --kustomize='': Process the kustomization directory. This flag can't be used together with -f or -R. -l, --labels='': Labels to apply to the service created by this call. --load-balancer-ip='': IP to assign to the LoadBalancer. If empty, an ephemeral IP will be created and used (cloud-provider specific). --name='': The name for the newly created object. -o, --output='': Output format. One of: json|yaml|name|go-template|go-template-file|template|templatefile|jsonpath|jsonpath-file. --overrides='': An inline JSON override for the generated object. If this is non-empty, it is used to override the generated object. Requires that the object supply a valid apiVersion field. --port='': The port that the service should serve on. Copied from the resource being exposed, if unspecified --protocol='': The network protocol for the service to be created. Default is 'TCP'. --record=false: Record current kubectl command in the resource annotation. If set to false, do not record the command. If set to true, record the command. If not set, default to updating the existing annotation value only if one already exists. -R, --recursive=false: Process the directory used in -f, --filename recursively. Useful when you want to manage related manifests organized within the same directory. --save-config=false: If true, the configuration of current object will be saved in its annotation. Otherwise, the annotation will be unchanged. This flag is useful when you want to perform kubectl apply on this object in the future. --selector='': A label selector to use for this service. Only equality-based selector requirements are supported. If empty (the default) infer the selector from the replication controller or replica set.) --session-affinity='': If non-empty, set the session affinity for the service to this; legal values: 'None', 'ClientIP' --target-port='': Name or number for the port on the container that the service should direct traffic to. Optional. --template='': Template string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview]. --type='': Type for this service: ClusterIP, NodePort, LoadBalancer, or ExternalName. Default is 'ClusterIP'. Usage: kubectl expose (-f FILENAME | TYPE NAME) [--port=port] [--protocol=TCP|UDP|SCTP] [--target-port=number-or-name] [--name=name] [--external-ip=external-ip-of-service] [--type=type] [options] Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s04 ~]#
kubectl logs帮助信息
[root@mcwk8s04 ~]# kubectl logs -h Print the logs for a container in a pod or specified resource. If the pod has only one container, the container name is optional. Aliases: logs, log Examples: # Return snapshot logs from pod nginx with only one container kubectl logs nginx # Return snapshot logs from pod nginx with multi containers kubectl logs nginx --all-containers=true # Return snapshot logs from all containers in pods defined by label app=nginx kubectl logs -lapp=nginx --all-containers=true # Return snapshot of previous terminated ruby container logs from pod web-1 kubectl logs -p -c ruby web-1 # Begin streaming the logs of the ruby container in pod web-1 kubectl logs -f -c ruby web-1 # Begin streaming the logs from all containers in pods defined by label app=nginx kubectl logs -f -lapp=nginx --all-containers=true # Display only the most recent 20 lines of output in pod nginx kubectl logs --tail=20 nginx # Show all logs from pod nginx written in the last hour kubectl logs --since=1h nginx # Return snapshot logs from first container of a job named hello kubectl logs job/hello # Return snapshot logs from container nginx-1 of a deployment named nginx kubectl logs deployment/nginx -c nginx-1 Options: --all-containers=false: Get all containers' logs in the pod(s). -c, --container='': Print the logs of this container -f, --follow=false: Specify if the logs should be streamed. --ignore-errors=false: If watching / following pod logs, allow for any errors that occur to be non-fatal --limit-bytes=0: Maximum bytes of logs to return. Defaults to no limit. --max-log-requests=5: Specify maximum number of concurrent logs to follow when using by a selector. Defaults to 5. --pod-running-timeout=20s: The length of time (like 5s, 2m, or 3h, higher than zero) to wait until at least one pod is running -p, --previous=false: If true, print the logs for the previous instance of the container in a pod if it exists. -l, --selector='': Selector (label query) to filter on. --since=0s: Only return logs newer than a relative duration like 5s, 2m, or 3h. Defaults to all logs. Only one of since-time / since may be used. --since-time='': Only return logs after a specific date (RFC3339). Defaults to all logs. Only one of since-time / since may be used. --tail=-1: Lines of recent log file to display. Defaults to -1 with no selector, showing all log lines otherwise 10, if a selector is provided. --timestamps=false: Include timestamps on each line in the log output Usage: kubectl logs [-f] [-p] (POD | TYPE/NAME) [-c CONTAINER] [options] Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s04 ~]#
kubectl set 帮助信息
[root@mcwk8s03 ~]# kubectl set -h Configure application resources These commands help you make changes to existing application resources. Available Commands: env Update environment variables on a pod template image Update image of a pod template resources Update resource requests/limits on objects with pod templates selector Set the selector on a resource serviceaccount Update ServiceAccount of a resource subject Update User, Group or ServiceAccount in a RoleBinding/ClusterRoleBinding Usage: kubectl set SUBCOMMAND [options] Use "kubectl <command> --help" for more information about a given command. Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s03 ~]#
kubectl set image帮助信息
[root@mcwk8s03 ~]# kubectl set image -h Update existing container image(s) of resources. Possible resources include (case insensitive): pod (po), replicationcontroller (rc), deployment (deploy), daemonset (ds), replicaset (rs) Examples: # Set a deployment's nginx container image to 'nginx:1.9.1', and its busybox container image to 'busybox'. kubectl set image deployment/nginx busybox=busybox nginx=nginx:1.9.1 # Update all deployments' and rc's nginx container's image to 'nginx:1.9.1' kubectl set image deployments,rc nginx=nginx:1.9.1 --all # Update image of all containers of daemonset abc to 'nginx:1.9.1' kubectl set image daemonset abc *=nginx:1.9.1 # Print result (in yaml format) of updating nginx container image from local file, without hitting the server kubectl set image -f path/to/file.yaml nginx=nginx:1.9.1 --local -o yaml Options: --all=false: Select all resources, including uninitialized ones, in the namespace of the specified resource types --allow-missing-template-keys=true: If true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats. --dry-run=false: If true, only print the object that would be sent, without sending it. -f, --filename=[]: Filename, directory, or URL to files identifying the resource to get from a server. -k, --kustomize='': Process the kustomization directory. This flag can't be used together with -f or -R. --local=false: If true, set image will NOT contact api-server but run locally. -o, --output='': Output format. One of: json|yaml|name|go-template|go-template-file|template|templatefile|jsonpath|jsonpath-file. --record=false: Record current kubectl command in the resource annotation. If set to false, do not record the command. If set to true, record the command. If not set, default to updating the existing annotation value only if one already exists. -R, --recursive=false: Process the directory used in -f, --filename recursively. Useful when you want to manage related manifests organized within the same directory. -l, --selector='': Selector (label query) to filter on, not including uninitialized ones, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2) --template='': Template string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview]. Usage: kubectl set image (-f FILENAME | TYPE NAME) CONTAINER_NAME_1=CONTAINER_IMAGE_1 ... CONTAINER_NAME_N=CONTAINER_IMAGE_N [options] Use "kubectl options" for a list of global command-line options (applies to all commands). [root@mcwk8s03 ~]#
kubectl部署应用的周期
通过kubectl部署一个应用，他的生命周期如下，会经历如下过程。创建资源，发布应用，应用更新，应用回滚，以及应用删除。我们的应用一般都是直接构建好的镜像，然后直接就能部署。应用可以实现多个副本。
1、创建 kubectl run nginx --replicas=3 --image=nginx:1.14 --port=80 kubectl get deploy,pods 2、发布 kubectl expose deployment nginx --port=80 --type=NodePort --target-port=80 --name=nginx-service kubectl get service 3、更新 kubectl set image deployment/nginx nginx=nginx:1.15 4、回滚 kubectl rollout history deployment/nginx kubectl rollout undo deployment/nginx 5、删除 kubectl delete deploy/nginx kubectl delete svc/nginx-service
kubectl部署应用过程详解
kubectl run 运行容器
kubectl run NAME –image=image [–env=”key=value”] [–port=port] [–replicas=replicas] [–dry-run=bool] [–overrides=inline-json] [–command] — [COMMAND] [args…] [options]
NAM：容器的名称
–image：指定使用的镜像
–env：指定容器内的环境变量，
–port：指定容器中需要映射的端口，也就是需要暴露的服务的端口
–replicas：指定副本数
–dry-run：指定是创建还是测试用
–overrides：可以重写配置
–command ：可以替换容器启动时的命令。
[root@mcwk8s04 ~]# [root@mcwk8s04 ~]# kubectl run mcw-nginx-deployment --image=nginx --port=80 --replicas=3 kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead. deployment.apps/mcw-nginx-deployment created [root@mcwk8s04 ~]# [root@mcwk8s04 ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES mcw-nginx-deployment-86466dbd78-fkrs7 1/1 Running 0 27m 172.17.13.2 mcwk8s05 <none> <none> mcw-nginx-deployment-86466dbd78-rnvsc 1/1 Running 0 27m 172.17.13.4 mcwk8s05 <none> <none> mcw-nginx-deployment-86466dbd78-znjbm 1/1 Running 0 27m 172.17.21.3 mcwk8s06 <none> <none> [root@mcwk8s04 ~]#
kubectl get
指定查看多个资源
[root@mcwk8s04 ~]# kubectl get deploy,pods NAME READY UP-TO-DATE AVAILABLE AGE deployment.extensions/mcw-nginx-deployment 3/3 3 3 29m NAME READY STATUS RESTARTS AGE pod/mcw-nginx-deployment-86466dbd78-fkrs7 1/1 Running 0 29m pod/mcw-nginx-deployment-86466dbd78-rnvsc 1/1 Running 0 29m pod/mcw-nginx-deployment-86466dbd78-znjbm 1/1 Running 0 29m [root@mcwk8s04 ~]#
查看副本
[root@mcwk8s04 ~]# kubectl get replicasets NAME DESIRED CURRENT READY AGE mcw-nginx-deployment-86466dbd78 3 3 3 31m [root@mcwk8s04 ~]# kubectl get rs NAME DESIRED CURRENT READY AGE mcw-nginx-deployment-86466dbd78 3 3 3 31m [root@mcwk8s04 ~]#
kubectl expose 让pod提供对外服务
kubectl expose (-f FILENAME | TYPE NAME) [–port=port] [–protocol=TCP|UDP|SCTP] [–target-port=number-or-name] [–name=name] [–external-ip=external-ip-of-service] [–type=type] [options]
-f FILENAME | TYPE NAME ：可以是yaml文件，指定资源类型。
–port：指定暴露的端口，集群内访问service的端口
–protocol：指定service转发的协议类型
–target-port：容器内服务端口
–name ：指定service的名字
–type：指定service类型 ClusterIP, NodePort, LoadBalancer, or ExternalName
[root@mcwk8s04 ~]# kubectl expose deployment --port=80 --target-port=80 --name=mcw-nginx-service --type=NodePort error: resource(s) were provided, but no name, label selector, or --all flag specified See 'kubectl expose -h' for help and examples [root@mcwk8s04 ~]# kubectl get deployment NAME READY UP-TO-DATE AVAILABLE AGE mcw-nginx-deployment 3/3 3 3 54m [root@mcwk8s04 ~]# kubectl expose deployment mcw-nginx-deployment --port=80 --target-port=80 --name=mcw-nginx-service --type=NodePort service/mcw-nginx-service exposed [root@mcwk8s04 ~]# kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.2.0.1 <none> 443/TCP 5d19h mcw-nginx-service NodePort 10.2.0.252 <none> 80:39719/TCP 11s [root@mcwk8s04 ~]#
kubectl api-resources资源简写
[root@mcwk8s04 ~]# kubectl api-resources NAME SHORTNAMES APIGROUP NAMESPACED KIND bindings true Binding componentstatuses cs false ComponentStatus configmaps cm true ConfigMap endpoints ep true Endpoints events ev true Event limitranges limits true LimitRange namespaces ns false Namespace nodes no false Node persistentvolumeclaims pvc true PersistentVolumeClaim persistentvolumes pv false PersistentVolume pods po true Pod podtemplates true PodTemplate replicationcontrollers rc true ReplicationController resourcequotas quota true ResourceQuota secrets true Secret serviceaccounts sa true ServiceAccount services svc true Service mutatingwebhookconfigurations admissionregistration.k8s.io false MutatingWebhookConfiguration validatingwebhookconfigurations admissionregistration.k8s.io false ValidatingWebhookConfiguration customresourcedefinitions crd,crds apiextensions.k8s.io false CustomResourceDefinition apiservices apiregistration.k8s.io false APIService controllerrevisions apps true ControllerRevision daemonsets ds apps true DaemonSet deployments deploy apps true Deployment replicasets rs apps true ReplicaSet statefulsets sts apps true StatefulSet tokenreviews authentication.k8s.io false TokenReview localsubjectaccessreviews authorization.k8s.io true LocalSubjectAccessReview selfsubjectaccessreviews authorization.k8s.io false SelfSubjectAccessReview selfsubjectrulesreviews authorization.k8s.io false SelfSubjectRulesReview subjectaccessreviews authorization.k8s.io false SubjectAccessReview horizontalpodautoscalers hpa autoscaling true HorizontalPodAutoscaler cronjobs cj batch true CronJob jobs batch true Job certificatesigningrequests csr certificates.k8s.io false CertificateSigningRequest leases coordination.k8s.io true Lease events ev events.k8s.io true Event daemonsets ds extensions true DaemonSet deployments deploy extensions true Deployment ingresses ing extensions true Ingress networkpolicies netpol extensions true NetworkPolicy podsecuritypolicies psp extensions false PodSecurityPolicy replicasets rs extensions true ReplicaSet ingresses ing networking.k8s.io true Ingress networkpolicies netpol networking.k8s.io true NetworkPolicy runtimeclasses node.k8s.io false RuntimeClass poddisruptionbudgets pdb policy true PodDisruptionBudget podsecuritypolicies psp policy false PodSecurityPolicy clusterrolebindings rbac.authorization.k8s.io false ClusterRoleBinding clusterroles rbac.authorization.k8s.io false ClusterRole rolebindings rbac.authorization.k8s.io true RoleBinding roles rbac.authorization.k8s.io true Role priorityclasses pc scheduling.k8s.io false PriorityClass csidrivers storage.k8s.io false CSIDriver csinodes storage.k8s.io false CSINode storageclasses sc storage.k8s.io false StorageClass volumeattachments storage.k8s.io false VolumeAttachment [root@mcwk8s04 ~]#
service的三种端口
port
service暴露在cluster ip上的端口，:port 是提供给集群内部客户访问service的入口。
nodePort
nodePort是k8s提供给集群外部客户访问service入口的一种方式，:nodePort 是提供给集群外部客户访问service的入口。
targetPort
targetPort是pod上的端口，从port和nodePort上到来的数据最终经过kube-proxy流入到后端pod的targetPort上进入容器。
port、nodePort总结
总的来说，port和nodePort都是service的端口，前者暴露给集群内客户访问服务，后者暴露给集群外客户访问服务。从这两个端口到来的数据都需要经过反向代理kube-proxy流入后端pod的targetPod，从而到达pod上的容器内。
查看service转发情况ipvadm
service NodePort 39719 和endpoint [root@mcwk8s03 ~]# kubectl get svc mcw-nginx-service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE mcw-nginx-service NodePort 10.2.0.252 <none> 80:39719/TCP 9m21s [root@mcwk8s03 ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES mcw-nginx-deployment-86466dbd78-fkrs7 1/1 Running 0 64m 172.17.13.2 mcwk8s05 <none> <none> mcw-nginx-deployment-86466dbd78-rnvsc 1/1 Running 0 64m 172.17.13.4 mcwk8s05 <none> <none> mcw-nginx-deployment-86466dbd78-znjbm 1/1 Running 0 64m 172.17.21.3 mcwk8s06 <none> <none> [root@mcwk8s03 ~]# [root@mcwk8s03 ~]# kubectl get endpoints mcw-nginx-service NAME ENDPOINTS AGE mcw-nginx-service 172.17.13.2:80,172.17.13.4:80,172.17.21.3:80 12m [root@mcwk8s03 ~]# node上查看nodeport [root@mcwk8s05 ~]# netstat -lntup|grep 39719 tcp6 0 0 :::39719 :::* LISTEN 130848/kube-proxy [root@mcwk8s05 ~]# node上使用ipvadm查看service的转发情况(负载均衡情况) [root@mcwk8s05 ~]# yum install ipvsadm -y [root@mcwk8s05 ~]# ipvsadm -L -n IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port Scheduler Flags -> RemoteAddress:Port Forward Weight ActiveConn InActConn TCP 10.0.0.35:39719 rr #node ip : node port 就转发到下面三个pod的80服务上 -> 172.17.13.2:80 Masq 1 0 0 -> 172.17.13.4:80 Masq 1 0 0 -> 172.17.21.3:80 Masq 1 0 0 ...... TCP 172.17.13.0:39719 rr -> 172.17.13.2:80 Masq 1 0 0 -> 172.17.13.4:80 Masq 1 0 0 -> 172.17.21.3:80 Masq 1 0 0 ...... TCP 172.17.13.1:39719 rr -> 172.17.13.2:80 Masq 1 0 0 -> 172.17.13.4:80 Masq 1 0 0 -> 172.17.21.3:80 Masq 1 0 0 .......
TCP 10.2.0.252:80 rr #service的cluster ip : port 提供集群内部访问service用的，这个端口和宿主机端口没关系，不是宿主机端口
-> 172.17.13.2:80 Masq 1 0 0
-> 172.17.13.4:80 Masq 1 0 0
-> 172.17.21.3:80 Masq 1 0 0
[root@mcwk8s05 ~]#
浏览器上访问时
谷歌浏览器成功访问，被调度到其中一个pod上了
kubectl set 更新应用
使用k8s，使用的是镜像。我们需要更新应用，就是换新的镜像。kubectl set可以替换镜像。它还有一些子命令
env Update environment variables on a pod template
image Update image of a pod template
resources 可以对资源，比如cpu等进行限制，Update resource requests/limits on objects with pod templates
selector 修改标签，Set the selector on a resource
serviceaccount Update ServiceAccount of a resource
subject 角色绑定 。Update User, Group or ServiceAccount in a RoleBinding/ClusterRoleBinding
kubectl -h
kubectl set -h
kubectl set image -h
我们可以层层去看帮助信息，找到我们需要的命令。
比如我们就用下面的改改，
当我们请求网站的时候，响应头里面带了服务的版本信息
我们将nginx改为1.14版本的镜像
kubectl set image deployment/nginx busybox=busybox nginx=nginx:1.9.1
根据帮助信息里的修改，deployment名字要对上。后面容器名字=新的镜像要对上容器名，把pod后面的随机字符串去掉就行。貌似也就是deployment名称呀。-w会实时显示pod的情况
不知道为啥，master上执行命令，拉取镜像很慢，拉取不下来，但是我直接取node上docker pull很快的。可能是node上直接用的配置文件里面的三个镜像地址，而kubectl去拉去镜像，用的是k8s集群里哪里设置的一个镜像地址吧？我记得之前设置了一个阿里云镜像地址的。所以我直接就在node上执行命令拉取镜像了。让pod不用显示拉取镜像这一个步骤了。
-w可能理解有误，我这直接去node上执行命令pull镜像之后，貌似已经运行了，但是-w这里还是那里卡着不动。
我们再次去浏览器上的响应头里看，发现已经成了我们修改的1.14版本了
我们层层查看，就用这个命令来查看版本
[root@mcwk8s04 ~]# kubectl get deploy NAME READY UP-TO-DATE AVAILABLE AGE mcw-nginx-deployment 3/3 3 3 3h54m [root@mcwk8s04 ~]# kubectl rollout history deployment/mcw-nginx-deployment deployment.extensions/mcw-nginx-deployment REVISION CHANGE-CAUSE 1 <none> 2 <none> [root@mcwk8s04 ~]#
回滚到上一个版本以及查看回滚的状态
[root@mcwk8s04 ~]# kubectl rollout undo deployment/mcw-nginx-deployment deployment.extensions/mcw-nginx-deployment rolled back [root@mcwk8s04 ~]# kubectl rollout status deployment/mcw-nginx-deployment Waiting for deployment "mcw-nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 2 out of 3 new replicas have been updated... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 2 old replicas are pending termination... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 1 old replicas are pending termination... Waiting for deployment "mcw-nginx-deployment" rollout to finish: 1 old replicas are pending termination... deployment "mcw-nginx-deployment" successfully rolled out [root@mcwk8s04 ~]# kubectl rollout status deployment/mcw-nginx-deployment deployment "mcw-nginx-deployment" successfully rolled out [root@mcwk8s04 ~]#
再刷新一下，页面上已经显示之前的那个版本了
删除资源
[root@mcwk8s04 ~]# kubectl get deploy NAME READY UP-TO-DATE AVAILABLE AGE mcw-nginx-deployment 3/3 3 3 4h1m [root@mcwk8s04 ~]# kubectl delete deploy mcw-nginx-deployment deployment.extensions "mcw-nginx-deployment" deleted [root@mcwk8s04 ~]# kubectl get pod NAME READY STATUS RESTARTS AGE mcw-nginx-deployment-86466dbd78-8r5wr 0/1 Terminating 0 4m23s [root@mcwk8s04 ~]# kubectl get pod No resources found. [root@mcwk8s04 ~]# kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.2.0.1 <none> 443/TCP 5d22h mcw-nginx-service NodePort 10.2.0.252 <none> 80:39719/TCP 3h6m [root@mcwk8s04 ~]# kubectl delete svc mcw-nginx-service service "mcw-nginx-service" deleted [root@mcwk8s04 ~]# kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.2.0.1 <none> 443/TCP 5d22h [root@mcwk8s04 ~]#
查看所有的接口的版本
apps/v1 v1是稳定版 v1beta1,2是测试版 。这是http资源。我们生产一般不用测试版本api接口
[root@mcwk8s04 ~]# kubectl api-versions admissionregistration.k8s.io/v1beta1 apiextensions.k8s.io/v1beta1 apiregistration.k8s.io/v1 apiregistration.k8s.io/v1beta1 apps/v1 apps/v1beta1 apps/v1beta2 authentication.k8s.io/v1 authentication.k8s.io/v1beta1 authorization.k8s.io/v1 authorization.k8s.io/v1beta1 autoscaling/v1 autoscaling/v2beta1 autoscaling/v2beta2 batch/v1 batch/v1beta1 certificates.k8s.io/v1beta1 coordination.k8s.io/v1 coordination.k8s.io/v1beta1 events.k8s.io/v1beta1 extensions/v1beta1 networking.k8s.io/v1 networking.k8s.io/v1beta1 node.k8s.io/v1beta1 policy/v1beta1 rbac.authorization.k8s.io/v1 rbac.authorization.k8s.io/v1beta1 scheduling.k8s.io/v1 scheduling.k8s.io/v1beta1 storage.k8s.io/v1 storage.k8s.io/v1beta1 v1 [root@mcwk8s04 ~]#
通过yaml配置文件部署服务
我们在官网里一层层找，下面是各种资源模板
//kubernetes.io/docs/concepts/workloads/controllers/deployment/
这篇文档的这个部位，就是一个yaml的案例
将官网的复制过来，然后执行部署
[root@mcwk8s03 ~]# mkdir demo [root@mcwk8s03 ~]# cd demo/ [root@mcwk8s03 demo]# vim mcw-nginx-deployment.yaml [root@mcwk8s03 demo]# cat mcw-nginx-deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-deployment labels: app: nginx spec: replicas: 3 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:1.14.2 ports: - containerPort: 80 [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# kubectl create -f mcw-nginx-deployment.yaml deployment.apps/nginx-deployment created [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 5s nginx-deployment-7fd6966748-pgfgq 0/1 ContainerCreating 0 5s nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 5s [root@mcwk8s03 demo]# [root@mcwk8s03 demo]#
官网里面看其它资源的案例
部署service
[root@mcwk8s03 demo]# [root@mcwk8s03 demo]# vim mcw-nginx-service.yaml [root@mcwk8s03 demo]# cat mcw-nginx-service.yaml apiVersion: v1 kind: Service metadata: name: nginx-service labels: app: nginx spec: type: NodePort ports: - port: 80 targetPort: 80 selector: app: nginx [root@mcwk8s03 demo]# kubectl create -f mcw-nginx-service.yaml service/nginx-service created [root@mcwk8s03 demo]# kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.2.0.1 <none> 443/TCP 5d22h nginx-service NodePort 10.2.0.247 <none> 80:33851/TCP 4s [root@mcwk8s03 demo]#
访问上面刚刚部署的服务，版本也是对上的
YAML配置文件管理资源 实用技巧
• 用run命令生成
kubectl run –image=nginx my-deploy -o yaml –dry-run > my-deploy.yaml
• 用get命令导出
kubectl get my-deploy/nginx -o=yaml –export > my-deploy.yaml
• Pod容器的字段拼写忘记了
kubectl explain pods.spec.containers
用run命令生成 –dry-run生成配置文件
[root@mcwk8s03 demo]# kubectl run mcw-nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run #执行部署的命令后面接--dry-run，不会进行部署，可以检查是否有语法错误 kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead. deployment.apps/mcw-nginx-deployment created (dry run) [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 36m nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 36m nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 36m [root@mcwk8s03 demo]# kubectl get deploy NAME READY UP-TO-DATE AVAILABLE AGE nginx-deployment 3/3 3 3 37m [root@mcwk8s03 demo]#
[root@mcwk8s03 demo]# kubectl run mcw-nginx-deployment –image=nginx –port=80 –repli=3 –dry-run #如这条命令，副本数参数写错了就报错了
Error: unknown flag: –repli
Examples:
# Start a single instance of nginx.
kubectl run nginx –image=nginx
–dry-run 不执行 -o指定输出格式，然后追加到文件中。这样可以生成yaml配置文件，我们就不需要去网上找模板了。将导出的模板多余的部分删除掉就行了。我们也可以获取到json格式的数据
[root@mcwk8s03 demo]# kubectl run mcw-nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o yaml >mcwTest.yaml kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead. [root@mcwk8s03 demo]# cat mcwTest.yaml apiVersion: apps/v1 kind: Deployment metadata: creationTimestamp: null labels: run: mcw-nginx-deployment name: mcw-nginx-deployment spec: replicas: 3 selector: matchLabels: run: mcw-nginx-deployment strategy: {} template: metadata: creationTimestamp: null labels: run: mcw-nginx-deployment spec: containers: - image: nginx name: mcw-nginx-deployment ports: - containerPort: 80 resources: {} status: {} [root@mcwk8s03 demo]# kubectl run mcw-nginx-deployment --image=nginx --port=80 --replicas=3 --dry-run -o json >mcwTest.json kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead. [root@mcwk8s03 demo]# cat mcwTest.json { "kind": "Deployment", "apiVersion": "apps/v1", "metadata": { "name": "mcw-nginx-deployment", "creationTimestamp": null, "labels": { "run": "mcw-nginx-deployment" } }, "spec": { "replicas": 3, "selector": { "matchLabels": { "run": "mcw-nginx-deployment" } }, "template": { "metadata": { "creationTimestamp": null, "labels": { "run": "mcw-nginx-deployment" } }, "spec": { "containers": [ { "name": "mcw-nginx-deployment", "image": "nginx", "ports": [ { "containerPort": 80 } ], "resources": {} } ] } }, "strategy": {} }, "status": {} } [root@mcwk8s03 demo]#
如下，大部分资源都可以用这种方式生成
[root@mcwk8s03 demo]# kubectl api-resources NAME SHORTNAMES APIGROUP NAMESPACED KIND bindings true Binding componentstatuses cs false ComponentStatus configmaps cm true ConfigMap endpoints ep true Endpoints events ev true Event limitranges limits true LimitRange namespaces ns false Namespace nodes no false Node persistentvolumeclaims pvc true PersistentVolumeClaim persistentvolumes pv false PersistentVolume pods po true Pod podtemplates true PodTemplate replicationcontrollers rc true ReplicationController resourcequotas quota true ResourceQuota secrets true Secret serviceaccounts sa true ServiceAccount services svc true Service mutatingwebhookconfigurations admissionregistration.k8s.io false MutatingWebhookConfiguration validatingwebhookconfigurations admissionregistration.k8s.io false ValidatingWebhookConfiguration customresourcedefinitions crd,crds apiextensions.k8s.io false CustomResourceDefinition apiservices apiregistration.k8s.io false APIService controllerrevisions apps true ControllerRevision daemonsets ds apps true DaemonSet deployments deploy apps true Deployment replicasets rs apps true ReplicaSet statefulsets sts apps true StatefulSet tokenreviews authentication.k8s.io false TokenReview localsubjectaccessreviews authorization.k8s.io true LocalSubjectAccessReview selfsubjectaccessreviews authorization.k8s.io false SelfSubjectAccessReview selfsubjectrulesreviews authorization.k8s.io false SelfSubjectRulesReview subjectaccessreviews authorization.k8s.io false SubjectAccessReview horizontalpodautoscalers hpa autoscaling true HorizontalPodAutoscaler cronjobs cj batch true CronJob jobs batch true Job certificatesigningrequests csr certificates.k8s.io false CertificateSigningRequest leases coordination.k8s.io true Lease events ev events.k8s.io true Event daemonsets ds extensions true DaemonSet deployments deploy extensions true Deployment ingresses ing extensions true Ingress networkpolicies netpol extensions true NetworkPolicy podsecuritypolicies psp extensions false PodSecurityPolicy replicasets rs extensions true ReplicaSet ingresses ing networking.k8s.io true Ingress networkpolicies netpol networking.k8s.io true NetworkPolicy runtimeclasses node.k8s.io false RuntimeClass poddisruptionbudgets pdb policy true PodDisruptionBudget podsecuritypolicies psp policy false PodSecurityPolicy clusterrolebindings rbac.authorization.k8s.io false ClusterRoleBinding clusterroles rbac.authorization.k8s.io false ClusterRole rolebindings rbac.authorization.k8s.io true RoleBinding roles rbac.authorization.k8s.io true Role priorityclasses pc scheduling.k8s.io false PriorityClass csidrivers storage.k8s.io false CSIDriver csinodes storage.k8s.io false CSINode storageclasses sc storage.k8s.io false StorageClass volumeattachments storage.k8s.io false VolumeAttachment [root@mcwk8s03 demo]#
用get命令导出已部署资源的配置，然后我们也可以据此修改
把不熟悉的，没有的删除掉
[root@mcwk8s03 demo]# kubectl get deploy NAME READY UP-TO-DATE AVAILABLE AGE nginx-deployment 3/3 3 3 51m [root@mcwk8s03 demo]# kubectl get deploy/nginx-deployment --export -o yaml Flag --export has been deprecated, This flag is deprecated and will be removed in future. apiVersion: extensions/v1beta1 kind: Deployment metadata: annotations: deployment.kubernetes.io/revision: "1" creationTimestamp: null generation: 1 labels: app: nginx name: nginx-deployment selfLink: /apis/extensions/v1beta1/namespaces/default/deployments/nginx-deployment spec: progressDeadlineSeconds: 600 replicas: 3 revisionHistoryLimit: 10 selector: matchLabels: app: nginx strategy: rollingUpdate: maxSurge: 25% maxUnavailable: 25% type: RollingUpdate template: metadata: creationTimestamp: null labels: app: nginx spec: containers: - image: nginx:1.14.2 imagePullPolicy: IfNotPresent name: nginx ports: - containerPort: 80 protocol: TCP resources: {} terminationMessagePath: /dev/termination-log terminationMessagePolicy: File dnsPolicy: ClusterFirst restartPolicy: Always schedulerName: default-scheduler securityContext: {} terminationGracePeriodSeconds: 30 status: {} [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# kubectl get deploy/nginx-deployment --export -o=yaml Flag --export has been deprecated, This flag is deprecated and will be removed in future. apiVersion: extensions/v1beta1 kind: Deployment metadata: annotations: deployment.kubernetes.io/revision: "1" creationTimestamp: null generation: 1 labels: app: nginx name: nginx-deployment selfLink: /apis/extensions/v1beta1/namespaces/default/deployments/nginx-deployment spec: progressDeadlineSeconds: 600 replicas: 3 revisionHistoryLimit: 10 selector: matchLabels: app: nginx strategy: rollingUpdate: maxSurge: 25% maxUnavailable: 25% type: RollingUpdate template: metadata: creationTimestamp: null labels: app: nginx spec: containers: - image: nginx:1.14.2 imagePullPolicy: IfNotPresent name: nginx ports: - containerPort: 80 protocol: TCP resources: {} terminationMessagePath: /dev/termination-log terminationMessagePolicy: File dnsPolicy: ClusterFirst restartPolicy: Always schedulerName: default-scheduler securityContext: {} terminationGracePeriodSeconds: 30 status: {} [root@mcwk8s03 demo]# kubectl get deploy/nginx-deployment --export -o=yaml >myGet.yaml Flag --export has been deprecated, This flag is deprecated and will be removed in future. [root@mcwk8s03 demo]# head -3 myGet.yaml apiVersion: extensions/v1beta1 kind: Deployment metadata: [root@mcwk8s03 demo]#
Pod容器的字段拼写忘记了explain
比如我们忘了哪个字段是怎么拼写了可以像下面这样找到
[root@mcwk8s03 demo]# kubectl explain pods.spec.containers KIND: Pod VERSION: v1 RESOURCE: containers <[]Object> DESCRIPTION: List of containers belonging to the pod. Containers cannot currently be added or removed. There must be at least one container in a Pod. Cannot be updated. A single application container that you want to run within a pod. FIELDS: args <[]string> Arguments to the entrypoint. The docker image's CMD is used if this is not provided. Variable references $(VAR_NAME) are expanded using the container's environment. If a variable cannot be resolved, the reference in the input string will be unchanged. The $(VAR_NAME) syntax can be escaped with a double $$, ie: $$(VAR_NAME). Escaped references will never be expanded, regardless of whether the variable exists or not. Cannot be updated. More info: https://kubernetes.io/docs/tasks/inject-data-application/define-command-argument-container/#running-a-command-in-a-shell command <[]string> Entrypoint array. Not executed within a shell. The docker image's ENTRYPOINT is used if this is not provided. Variable references $(VAR_NAME) are expanded using the container's environment. If a variable cannot be resolved, the reference in the input string will be unchanged. The $(VAR_NAME) syntax can be escaped with a double $$, ie: $$(VAR_NAME). Escaped references will never be expanded, regardless of whether the variable exists or not. Cannot be updated. More info: https://kubernetes.io/docs/tasks/inject-data-application/define-command-argument-container/#running-a-command-in-a-shell env <[]Object> List of environment variables to set in the container. Cannot be updated. envFrom <[]Object> List of sources to populate environment variables in the container. The keys defined within a source must be a C_IDENTIFIER. All invalid keys will be reported as an event when the container is starting. When a key exists in multiple sources, the value associated with the last source will take precedence. Values defined by an Env with a duplicate key will take precedence. Cannot be updated. image <string> Docker image name. More info: https://kubernetes.io/docs/concepts/containers/images This field is optional to allow higher level config management to default or override container images in workload controllers like Deployments and StatefulSets. imagePullPolicy <string> Image pull policy. One of Always, Never, IfNotPresent. Defaults to Always if :latest tag is specified, or IfNotPresent otherwise. Cannot be updated. More info: https://kubernetes.io/docs/concepts/containers/images#updating-images lifecycle <Object> Actions that the management system should take in response to container lifecycle events. Cannot be updated. livenessProbe <Object> Periodic probe of container liveness. Container will be restarted if the probe fails. Cannot be updated. More info: https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle#container-probes name <string> -required- Name of the container specified as a DNS_LABEL. Each container in a pod must have a unique name (DNS_LABEL). Cannot be updated. ports <[]Object> List of ports to expose from the container. Exposing a port here gives the system additional information about the network connections a container uses, but is primarily informational. Not specifying a port here DOES NOT prevent that port from being exposed. Any port which is listening on the default "0.0.0.0" address inside a container will be accessible from the network. Cannot be updated. readinessProbe <Object> Periodic probe of container service readiness. Container will be removed from service endpoints if the probe fails. Cannot be updated. More info: https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle#container-probes resources <Object> Compute Resources required by this container. Cannot be updated. More info: https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/ securityContext <Object> Security options the pod should run with. More info: https://kubernetes.io/docs/concepts/policy/security-context/ More info: https://kubernetes.io/docs/tasks/configure-pod-container/security-context/ stdin <boolean> Whether this container should allocate a buffer for stdin in the container runtime. If this is not set, reads from stdin in the container will always result in EOF. Default is false. stdinOnce <boolean> Whether the container runtime should close the stdin channel after it has been opened by a single attach. When stdin is true the stdin stream will remain open across multiple attach sessions. If stdinOnce is set to true, stdin is opened on container start, is empty until the first client attaches to stdin, and then remains open and accepts data until the client disconnects, at which time stdin is closed and remains closed until the container is restarted. If this flag is false, a container processes that reads from stdin will never receive an EOF. Default is false terminationMessagePath <string> Optional: Path at which the file to which the container's termination message will be written is mounted into the container's filesystem. Message written is intended to be brief final status, such as an assertion failure message. Will be truncated by the node if greater than 4096 bytes. The total message length across all containers will be limited to 12kb. Defaults to /dev/termination-log. Cannot be updated. terminationMessagePolicy <string> Indicate how the termination message should be populated. File will use the contents of terminationMessagePath to populate the container status message on both success and failure. FallbackToLogsOnError will use the last chunk of container log output if the termination message file is empty and the container exited with an error. The log output is limited to 2048 bytes or 80 lines, whichever is smaller. Defaults to File. Cannot be updated. tty <boolean> Whether this container should allocate a TTY for itself, also requires 'stdin' to be true. Default is false. volumeDevices <[]Object> volumeDevices is the list of block devices to be used by the container. This is a beta feature. volumeMounts <[]Object> Pod volumes to mount into the container's filesystem. Cannot be updated. workingDir <string> Container's working directory. If not specified, the container runtime's default will be used, which might be configured in the container image. Cannot be updated. [root@mcwk8s03 demo]#
如下，找元数据下的标签的一个过程
[root@mcwk8s03 demo]# head mcwTest.yaml apiVersion: apps/v1 kind: Deployment metadata: creationTimestamp: null labels: run: mcw-nginx-deployment name: mcw-nginx-deployment spec: replicas: 3 selector: [root@mcwk8s03 demo]# kubectl explain pods KIND: Pod VERSION: v1 DESCRIPTION: Pod is a collection of containers that can run on a host. This resource is created by clients and scheduled onto hosts. FIELDS: apiVersion <string> APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#resources kind <string> Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kinds metadata <Object> Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata spec <Object> Specification of the desired behavior of the pod. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status status <Object> Most recently observed status of the pod. This data may not be up to date. Populated by the system. Read-only. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status [root@mcwk8s03 demo]# kubectl explain pods.metadata KIND: Pod VERSION: v1 RESOURCE: metadata <Object> DESCRIPTION: Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata ObjectMeta is metadata that all persisted resources must have, which includes all objects users must create. FIELDS: annotations <map[string]string> Annotations is an unstructured key value map stored with a resource that may be set by external tools to store and retrieve arbitrary metadata. They are not queryable and should be preserved when modifying objects. More info: http://kubernetes.io/docs/user-guide/annotations clusterName <string> The name of the cluster which the object belongs to. This is used to distinguish resources with same name and namespace in different clusters. This field is not set anywhere right now and apiserver is going to ignore it if set in create or update request. creationTimestamp <string> CreationTimestamp is a timestamp representing the server time when this object was created. It is not guaranteed to be set in happens-before order across separate operations. Clients may not set this value. It is represented in RFC3339 form and is in UTC. Populated by the system. Read-only. Null for lists. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata deletionGracePeriodSeconds <integer> Number of seconds allowed for this object to gracefully terminate before it will be removed from the system. Only set when deletionTimestamp is also set. May only be shortened. Read-only. deletionTimestamp <string> DeletionTimestamp is RFC 3339 date and time at which this resource will be deleted. This field is set by the server when a graceful deletion is requested by the user, and is not directly settable by a client. The resource is expected to be deleted (no longer visible from resource lists, and not reachable by name) after the time in this field, once the finalizers list is empty. As long as the finalizers list contains items, deletion is blocked. Once the deletionTimestamp is set, this value may not be unset or be set further into the future, although it may be shortened or the resource may be deleted prior to this time. For example, a user may request that a pod is deleted in 30 seconds. The Kubelet will react by sending a graceful termination signal to the containers in the pod. After that 30 seconds, the Kubelet will send a hard termination signal (SIGKILL) to the container and after cleanup, remove the pod from the API. In the presence of network partitions, this object may still exist after this timestamp, until an administrator or automated process can determine the resource is fully terminated. If not set, graceful deletion of the object has not been requested. Populated by the system when a graceful deletion is requested. Read-only. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata finalizers <[]string> Must be empty before the object is deleted from the registry. Each entry is an identifier for the responsible component that will remove the entry from the list. If the deletionTimestamp of the object is non-nil, entries in this list can only be removed. generateName <string> GenerateName is an optional prefix, used by the server, to generate a unique name ONLY IF the Name field has not been provided. If this field is used, the name returned to the client will be different than the name passed. This value will also be combined with a unique suffix. The provided value has the same validation rules as the Name field, and may be truncated by the length of the suffix required to make the value unique on the server. If this field is specified and the generated name exists, the server will NOT return a 409 - instead, it will either return 201 Created or 500 with Reason ServerTimeout indicating a unique name could not be found in the time allotted, and the client should retry (optionally after the time indicated in the Retry-After header). Applied only if Name is not specified. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#idempotency generation <integer> A sequence number representing a specific generation of the desired state. Populated by the system. Read-only. initializers <Object> An initializer is a controller which enforces some system invariant at object creation time. This field is a list of initializers that have not yet acted on this object. If nil or empty, this object has been completely initialized. Otherwise, the object is considered uninitialized and is hidden (in list/watch and get calls) from clients that haven't explicitly asked to observe uninitialized objects. When an object is created, the system will populate this list with the current set of initializers. Only privileged users may set or modify this list. Once it is empty, it may not be modified further by any user. DEPRECATED - initializers are an alpha field and will be removed in v1.15. labels <map[string]string> Map of string keys and values that can be used to organize and categorize (scope and select) objects. May match selectors of replication controllers and services. More info: http://kubernetes.io/docs/user-guide/labels managedFields <[]Object> ManagedFields maps workflow-id and version to the set of fields that are managed by that workflow. This is mostly for internal housekeeping, and users typically shouldn't need to set or understand this field. A workflow can be the user's name, a controller's name, or the name of a specific apply path like "ci-cd". The set of fields is always in the version that the workflow used when modifying the object. This field is alpha and can be changed or removed without notice. name <string> Name must be unique within a namespace. Is required when creating resources, although some resources may allow a client to request the generation of an appropriate name automatically. Name is primarily intended for creation idempotence and configuration definition. Cannot be updated. More info: http://kubernetes.io/docs/user-guide/identifiers#names namespace <string> Namespace defines the space within each name must be unique. An empty namespace is equivalent to the "default" namespace, but "default" is the canonical representation. Not all objects are required to be scoped to a namespace - the value of this field for those objects will be empty. Must be a DNS_LABEL. Cannot be updated. More info: http://kubernetes.io/docs/user-guide/namespaces ownerReferences <[]Object> List of objects depended by this object. If ALL objects in the list have been deleted, this object will be garbage collected. If this object is managed by a controller, then an entry in this list will point to this controller, with the controller field set to true. There cannot be more than one managing controller. resourceVersion <string> An opaque value that represents the internal version of this object that can be used by clients to determine when objects have changed. May be used for optimistic concurrency, change detection, and the watch operation on a resource or set of resources. Clients must treat these values as opaque and passed unmodified back to the server. They may only be valid for a particular resource or set of resources. Populated by the system. Read-only. Value must be treated as opaque by clients and . More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#concurrency-control-and-consistency selfLink <string> SelfLink is a URL representing this object. Populated by the system. Read-only. uid <string> UID is the unique in time and space value for this object. It is typically generated by the server on successful creation of a resource and is not allowed to change on PUT operations. Populated by the system. Read-only. More info: http://kubernetes.io/docs/user-guide/identifiers#uids [root@mcwk8s03 demo]# kubectl explain pods.metadata.labels KIND: Pod VERSION: v1 FIELD: labels <map[string]string> DESCRIPTION: Map of string keys and values that can be used to organize and categorize (scope and select) objects. May match selectors of replication controllers and services. More info: http://kubernetes.io/docs/user-guide/labels [root@mcwk8s03 demo]#
Pod容器分类
• Infrastructure Container：基础容器
• 维护整个Pod网络空间
• InitContainers：初始化容器
• 先于业务容器开始执行
• Containers：业务容器
• 并行启动
Infrastructure Container：基础容器
维护整个Pod网络空间
基础容器镜像的配置是在node节点上的kubelet的配置里。默认是找谷歌的，我们可以配置一个自己的镜像，改成自己的镜像地址。
InitContainers：初始化容器
先于业务容器开始执行
我们可以看下初始化容器是怎么用的。//kubernetes.io/docs/concepts/workloads/pods/init-containers/
业务之前做的操作，定义的时候和业务容器是同级配置的。比如服务注册，可以用到
Containers：业务容器
并行启动。就是我们部署好服务的pod
镜像拉取策略（imagePullPolicy）
IfNotPresent：默认值，镜像在宿主机上不存在时才拉取
Always：每次创建 Pod 都会重新拉取一次镜像
Never： Pod 永远不会主动拉取这个镜像
我们需要注意，run好像默认每次都拉取，apllay好像是不存在才拉取，如果仓库中最新的一直是latest，部署配置文件中没有修改，没加版本，注意可能不会拉取最新的镜像，还是用的node上的旧的镜像。
IfNotPresent：默认值，镜像在宿主机上不存在时才拉取
[root@mcwk8s03 demo]# cat mcwPod.yaml apiVersion: v1 kind: Pod metadata: name: mcwpod spec: containers: - name: nginx image: nginx imagePullPolicy: IfNotPresent [root@mcwk8s03 demo]# kubectl apply -f mcwPod.yaml pod/mcwpod created [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 0 6s nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 23h [root@mcwk8s03 demo]#
Always：每次创建 Pod 都会重新拉取一次镜像
run命令创建的好像默认是always
我们查看之前部署的，取策略
我们来创建一个pod
[root@mcwk8s03 demo]# cat mcwPod.yaml apiVersion: v1 kind: Pod metadata: name: mcwpod spec: containers: - name: nginx image: nginx imagePullPolicy: Always command: [ "echo","SUCCESS" ] [root@mcwk8s03 demo]# kubectl create -f mcwPod.yaml pod/mcwpod created [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 0/1 Completed 0 7s nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 23h [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 0/1 CrashLoopBackOff 3 68s nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 23h [root@mcwk8s03 demo]#
我们的启动命令替换了nginx的启动命令，导致无法启动成功了。去掉命令。apply重新部署
我们node节点上又镜像，但是它好像还是要去拉取用自己拉取的，我们master拉取镜像有点问题，不好拉取过来，暂时不等了。修改为IfNotPresent，看上面那个案例
[root@mcwk8s03 demo]# ls mcwPod.yaml mcwPod.yaml [root@mcwk8s03 demo]# cat mcwPod.yaml apiVersion: v1 kind: Pod metadata: name: mcwpod spec: containers: - name: nginx image: nginx imagePullPolicy: Always [root@mcwk8s03 demo]# kubectl apply -f mcwPod.yaml Warning: kubectl apply should be used on resource created by either kubectl create --save-config or kubectl apply pod/mcwpod configured [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 0/1 Completed 5 3m20s nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 23h [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 0/1 CrashLoopBackOff 5 5m53s nginx-deployment-7fd6966748-mxg8p 1/1 Running 0 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 0 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 0 23h [root@mcwk8s03 demo]# kubectl describe pod mcwpod|tail -9 Events: Type Reason Age From Message ---- ------ ---- ---- ------- Normal Scheduled 5m58s default-scheduler Successfully assigned default/mcwpod to mcwk8s05 Normal Pulled 5m5s (x4 over 5m54s) kubelet, mcwk8s05 Successfully pulled image "nginx" Normal Created 5m5s (x4 over 5m54s) kubelet, mcwk8s05 Created container nginx Normal Started 5m5s (x4 over 5m54s) kubelet, mcwk8s05 Started container nginx Normal Pulling 4m15s (x5 over 5m56s) kubelet, mcwk8s05 Pulling image "nginx" Warning BackOff 55s (x24 over 5m50s) kubelet, mcwk8s05 Back-off restarting failed container [root@mcwk8s03 demo]#
如下修改镜像版本，然后重新部署
[root@mcwk8s03 demo]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES mcwpod 1/1 Running 1 6m27s 172.17.64.2 mcwk8s05 <none> <none> nginx-deployment-7fd6966748-mxg8p 1/1 Running 1 23h 172.17.64.4 mcwk8s05 <none> <none> nginx-deployment-7fd6966748-pgfgq 0/1 Completed 0 23h <none> mcwk8s06 <none> <none> nginx-deployment-7fd6966748-wsfj4 0/1 Completed 0 23h <none> mcwk8s06 <none> <none> [root@mcwk8s03 demo]# curl -I 172.17.64.2 HTTP/1.1 200 OK Server: nginx/1.23.2 Date: Sun, 06 Nov 2022 13:01:04 GMT Content-Type: text/html Content-Length: 615 Last-Modified: Wed, 19 Oct 2022 07:56:21 GMT Connection: keep-alive ETag: "634fada5-267" Accept-Ranges: bytes [root@mcwk8s03 demo]# vim mcwPod.yaml [root@mcwk8s03 demo]# cat mcwPod.yaml apiVersion: v1 kind: Pod metadata: name: mcwpod spec: containers: - name: nginx image: nginx:1.14 imagePullPolicy: IfNotPresent [root@mcwk8s03 demo]# kubectl apply -f mcwPod.yaml pod/mcwpod configured [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 2 7m40s nginx-deployment-7fd6966748-mxg8p 1/1 Running 1 23h nginx-deployment-7fd6966748-pgfgq 1/1 Running 1 23h nginx-deployment-7fd6966748-wsfj4 1/1 Running 1 23h [root@mcwk8s03 demo]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES mcwpod 1/1 Running 2 7m50s 172.17.64.2 mcwk8s05 <none> <none> nginx-deployment-7fd6966748-mxg8p 1/1 Running 1 23h 172.17.64.4 mcwk8s05 <none> <none> nginx-deployment-7fd6966748-pgfgq 1/1 Running 1 23h 172.17.60.3 mcwk8s06 <none> <none> nginx-deployment-7fd6966748-wsfj4 1/1 Running 1 23h 172.17.60.2 mcwk8s06 <none> <none> [root@mcwk8s03 demo]# curl -I 172.17.64.2 HTTP/1.1 200 OK Server: nginx/1.14.2 #版本修改了 Date: Sun, 06 Nov 2022 13:02:18 GMT Content-Type: text/html Content-Length: 612 Last-Modified: Tue, 04 Dec 2018 14:44:49 GMT Connection: keep-alive ETag: "5c0692e1-264" Accept-Ranges: bytes [root@mcwk8s03 demo]#
Never： Pod 永远不会主动拉取这个镜像
imagePullSecrets
apiVersion: apps/v1 kind: Deployment metadata: name: tomcat-deployment labels: run: tomcat spec: replicas: 3 selector: matchLabels: run: tomcat template: metadata: labels: run: tomcat spec: imagePullSecrets: - name: registry-pull-secret containers: - name: tomcat image: 10.0.0.35/library/tomcat:v1 imagePullPolicy: Always ports: - containerPort: 8080 --- apiVersion: v1 kind: Service metadata: name: tomcat-service labels: run: tomcat spec: type: NodePort ports: - port: 80 targetPort: 8080 selector: run: tomcat
配置好的mcw-tomcat.yaml案例
当我们的仓库是私有仓库时，是需要登录才能pull镜像的，所以k8s配置文件中想拉取私有仓库，是需要配置访问凭证的，也就是下面的配置。如果仓库是公有的，是公开的仓库，那么不需要凭证，直接pull镜像的 。
imagePullSecrets:
- name: myregistrykey
我们看下node节点上的tomcat镜像
[root@mcwk8s05 harbor]# docker images tomcat:v1 REPOSITORY TAG IMAGE ID CREATED SIZE tomcat v1 3500a757f51d 4 days ago 473MB [root@mcwk8s05 harbor]#
我们用docker pull去harbor上拉取镜像前，需要登录仓库。如果我们写k8s配置文件，让它拉取镜像从我们自己部署的harbor上，那么也是需要凭证的。docker pull命令和k8s从harbor上拉取镜像的认证是不同的，不是你终端上执行docker login，然后aplay -f 就能拉取到镜像的 。元数据里面有标签，资源规格里面有匹配标签，pod模板元数据也有标签，标签要对于上，是个键值对。
下面我们用这个镜像来部署tomcat服务。下面是deployment和service
[root@mcwk8s03 demo]# cat mcw-tomcat.yaml apiVersion: apps/v1 kind: Deployment metadata: name: tomcat-deployment labels: run: tomcat spec: replicas: 3 selector: matchLabels: run: tomcat template: metadata: labels: run: tomcat spec: containers: - name: tomcat image: tomcat:v1 ports: - containerPort: 8080 --- apiVersion: v1 kind: Service metadata: name: tomcat-service labels: run: tomcat spec: type: NodePort ports: - port: 80 targetPort: 8080 selector: run: tomcat [root@mcwk8s03 demo]#
我们创建一下。用create显示错误，如果用apply部署，已经存在的不是显示错误，而是重新配置。
[root@mcwk8s03 demo]# kubectl create -f mcw-tomcat.yaml service/tomcat-service created Error from server (AlreadyExists): error when creating "mcw-tomcat.yaml": deployments.apps "tomcat-deployment" already exists [root@mcwk8s03 demo]#
[root@mcwk8s03 demo]# kubectl apply -f mcw-tomcat.yaml Warning: kubectl apply should be used on resource created by either kubectl create --save-config or kubectl apply deployment.apps/tomcat-deployment configured Warning: kubectl apply should be used on resource created by either kubectl create --save-config or kubectl apply service/tomcat-service configured [root@mcwk8s03 demo]#
我们看下，tomcat已经部署起来了。
[root@mcwk8s03 demo]# kubectl get deploy,pod,svc NAME READY UP-TO-DATE AVAILABLE AGE deployment.extensions/nginx-deployment 3/3 3 3 47h deployment.extensions/tomcat-deployment 3/3 3 3 7m6s NAME READY STATUS RESTARTS AGE pod/mcwpod 1/1 Running 3 24h pod/nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 47h pod/nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 47h pod/nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 47h pod/tomcat-deployment-7bbd6dc5cf-9kvp6 1/1 Running 0 7m5s pod/tomcat-deployment-7bbd6dc5cf-rvhhh 1/1 Running 0 7m5s pod/tomcat-deployment-7bbd6dc5cf-svfvr 1/1 Running 0 7m5s NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE service/kubernetes ClusterIP 10.2.0.1 <none> 443/TCP 7d21h service/nginx-service NodePort 10.2.0.247 <none> 80:33851/TCP 47h service/tomcat-service NodePort 10.2.0.30 <none> 80:49516/TCP 3m6s [root@mcwk8s03 demo]#
我们访问一下：没有找到
我们已经访问到tomcat了，只是我们的镜像里没有tomcat的测试页面，站点目录是空的。上面的如果本地没有镜像时是从docker hub等镜像站点上拉取的
现在我们要使用私有镜像仓库地址。我们仓库中有这个镜像
[root@mcwk8s05 harbor]# docker images 10.0.0.35/library/tomcat:v1 REPOSITORY TAG IMAGE ID CREATED SIZE 10.0.0.35/library/tomcat v1 3500a757f51d 4 days ago 473MB [root@mcwk8s05 harbor]#
我们将镜像改为私有仓库地址，镜像拉取策略改为总是拉取
修改后的如下：
[root@mcwk8s03 demo]# cat mcw-tomcat.yaml apiVersion: apps/v1 kind: Deployment metadata: name: tomcat-deployment labels: run: tomcat spec: replicas: 3 selector: matchLabels: run: tomcat template: metadata: labels: run: tomcat spec: containers: - name: tomcat image: 10.0.0.35/library/tomcat:v1 imagePullPolicy: Always ports: - containerPort: 8080 --- apiVersion: v1 kind: Service metadata: name: tomcat-service labels: run: tomcat spec: type: NodePort ports: - port: 80 targetPort: 8080 selector: run: tomcat [root@mcwk8s03 demo]#
我们将node上的镜像先删除，防止影响判断
[root@mcwk8s05 harbor]# docker images 10.0.0.35/library/tomcat:v1
REPOSITORY TAG IMAGE ID CREATED SIZE
10.0.0.35/library/tomcat v1 3500a757f51d 4 days ago 473MB
[root@mcwk8s05 harbor]#
[root@mcwk8s05 harbor]# docker rmi 10.0.0.35/library/tomcat:v1
Untagged: 10.0.0.35/library/tomcat:v1
[root@mcwk8s05 harbor]# docker images 10.0.0.35/library/tomcat:v1
REPOSITORY TAG IMAGE ID CREATED SIZE
[root@mcwk8s05 harbor]#
刚刚好像拉取没有经过登录，直接就拉取了。去node上执行一下，果然是不用登录就拉取成功了
我们去仓库看一下，是公有的，那么我们改成私有的试一下
取消勾选，点击保存
已成功改为私有
我们再次去node上执行，发现不能pull了，提示需要登录
现在我们再去执行tomcat部署，我们直接执行就行。因为我们已经改为了私有仓库镜像tomcat，总是拉取镜像
配置文件没有修改好像还是不会重新部署。那就将镜像改成别的版本镜像，部署成功后，再改回私有仓库镜像
[root@mcwk8s03 demo]# kubectl apply -f mcw-tomcat.yaml deployment.apps/tomcat-deployment unchanged service/tomcat-service unchanged [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 3 24h nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 47h nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 47h nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 47h tomcat-deployment-b4665695f-h2tpz 1/1 Running 0 13m tomcat-deployment-b4665695f-lr2cq 1/1 Running 0 13m tomcat-deployment-b4665695f-qrt4d 1/1 Running 0 13m [root@mcwk8s03 demo]#
下面我们就看到效果了。拉取镜像错误了。它会一直卡在这里，无法拉取到镜像。因为是滚动升级的，这一个没有成功更新，其它的也不会开始更新部署
[root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 3 24h nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 47h nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 47h nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 47h tomcat-deployment-7bbd6dc5cf-794zg 1/1 Running 0 87s tomcat-deployment-7bbd6dc5cf-nx9bq 1/1 Running 0 88s tomcat-deployment-7bbd6dc5cf-zx498 1/1 Running 0 91s [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# kubectl apply -f mcw-tomcat.yaml deployment.apps/tomcat-deployment configured service/tomcat-service unchanged [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 3 24h nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 47h nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 47h nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 47h tomcat-deployment-7bbd6dc5cf-794zg 1/1 Running 0 108s tomcat-deployment-7bbd6dc5cf-nx9bq 1/1 Running 0 109s tomcat-deployment-7bbd6dc5cf-zx498 1/1 Running 0 112s tomcat-deployment-b4665695f-hmkc7 0/1 ErrImagePull 0 7s [root@mcwk8s03 demo]#
我们看下事件日志，可以看到拉取镜像失败，可以需要登录或者不存在
Warning Failed 4m17s (x4 over 5m39s) kubelet, mcwk8s05 Failed to pull image “10.0.0.35/library/tomcat:v1”: rpc error: code = Unknown desc = Error response from daemon: pull access denied for 10.0.0.35/library/tomcat, repository does not exist or may require ‘docker login’: denied: requested access to the resource is denied
Warning Failed 4m17s (x4 over 5m39s) kubelet, mcwk8s05 Error: ErrImagePull
在我们的harbor主机上会生成这个文件 .docker/config.json 。也就是拿着这个凭证就可以去请求harbor了
[root@mcwk8s05 ~]# ls anaconda-ks.cfg harbor kubelet.sh mcw.tar node.zip proxy.sh [root@mcwk8s05 ~]# ls .docker/ config.json [root@mcwk8s05 ~]# cat .docker/config.json { "auths": { "10.0.0.35": { "auth": "bWFjaGFuZ3dlaTpBU2RmNTU2NDMzMzc3KiYm" } } }[root@mcwk8s05 ~]# ps -ef|grep harbor root 5449 99253 0 21:50 pts/0 00:00:00 grep --color=auto harbor root 109494 109408 0 10:03 ? 00:00:00 /bin/sh /harbor/start.sh root 109728 109494 0 10:03 ? 00:00:00 sudo -E -u #10000 /harbor/harbor_jobservice -c /etc/jobservice/config.yml 10000 109731 109728 0 10:03 ? 00:00:40 /harbor/harbor_jobservice -c /etc/jobservice/config.yml root 111021 110975 0 10:04 ? 00:00:00 /bin/sh /harbor/start.sh root 111120 111021 0 10:04 ? 00:00:00 sudo -E -u #10000 /harbor/harbor_adminserver 10000 111122 111120 0 10:04 ? 00:00:03 /harbor/harbor_adminserver root 111210 111191 0 10:04 ? 00:00:00 /bin/sh /harbor/start.sh root 111283 111210 0 10:04 ? 00:00:00 sudo -E -u #10000 /harbor/harbor_ui 10000 111284 111283 0 10:04 ? 00:00:10 /harbor/harbor_ui [root@mcwk8s05 ~]#
不过我们不能直接就用这个配置文件，我们需要编码一下。 -w 0，不换行。
[root@mcwk8s05 ~]# cat .docker/config.json | base64 -w 0 ewoJImF1dGhzIjogewoJCSIxMC4wLjAuMzUiOiB7CgkJCSJhdXRoIjogImJXRmphR0Z1WjNkbGFUcEJVMlJtTlRVMk5ETXpNemMzS2lZbSIKCQl9Cgl9Cn0=[root@mcwk8s05 ~]#
有了这个编码的字符串，我们就可以创建一个凭据资源了。官网里案例。其实就是一个secret资源，然后将我们在harbor主机获得的这个编码字符串,替换到下面docker配置json下
我们这里创建的资源不需要指定命名空间，就是默认的。替换如下；
[root@mcwk8s03 demo]# vim registry-pull-secret.yaml [root@mcwk8s03 demo]# cat registry-pull-secret.yaml apiVersion: v1 kind: Secret metadata: name: registry-pull-secret data: .dockerconfigjson: ewoJImF1dGhzIjogewoJCSIxMC4wLjAuMzUiOiB7CgkJCSJhdXRoIjogImJXRmphR0Z1WjNkbGFUcEJVMlJtTlRVMk5ETXpNemMzS2lZbSIKCQl9Cgl9Cn0= type: kubernetes.io/dockerconfigjson [root@mcwk8s03 demo]#
创建资源。数字是1，如果是0的话说明没有保存进去
[root@mcwk8s03 demo]# kubectl create -f registry-pull-secret.yaml secret/registry-pull-secret created [root@mcwk8s03 demo]# kubectl get secret NAME TYPE DATA AGE default-token-j9l4k kubernetes.io/service-account-token 3 4d23h registry-pull-secret kubernetes.io/dockerconfigjson 1 9s [root@mcwk8s03 demo]#
我们就用registry-pull-secret这个secret名字，在我们需要拉取私有仓库镜像的部署配置文件里引用
通过时间我们就能看出，是刚刚创建的pod，是用我们私有仓库的镜像。配置后可以登录私有仓库去拉取镜像
注意，它是跟容器是同级配置的。因为是对下面所有容器都生效，都能通过它拉取私有仓库镜像
[root@mcwk8s03 demo]# grep -A 4 imagePullSecrets mcw-tomcat.yaml imagePullSecrets: - name: registry-pull-secret containers: - name: tomcat image: 10.0.0.35/library/tomcat:v1 [root@mcwk8s03 demo]# [root@mcwk8s03 demo]# kubectl apply -f mcw-tomcat.yaml deployment.apps/tomcat-deployment configured service/tomcat-service unchanged [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 3 25h nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 2d nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 2d nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 2d tomcat-deployment-5fc76bc699-s5jds 0/1 ContainerCreating 0 4s tomcat-deployment-7bbd6dc5cf-794zg 1/1 Running 0 32m tomcat-deployment-7bbd6dc5cf-nx9bq 1/1 Running 0 32m tomcat-deployment-7bbd6dc5cf-zx498 1/1 Running 0 32m [root@mcwk8s03 demo]# kubectl get pod NAME READY STATUS RESTARTS AGE mcwpod 1/1 Running 3 25h nginx-deployment-7fd6966748-mxg8p 1/1 Running 2 2d nginx-deployment-7fd6966748-pgfgq 1/1 Running 2 2d nginx-deployment-7fd6966748-wsfj4 1/1 Running 2 2d tomcat-deployment-5fc76bc699-lrrbc 1/1 Running 0 30s tomcat-deployment-5fc76bc699-s5jds 1/1 Running 0 54s tomcat-deployment-5fc76bc699-vbqpf 1/1 Running 0 28s [root@mcwk8s03 demo]#
我们这里也是增加了下载次数，因为我们是三个副本，每个都是总是拉取镜像的，所以没执行成功一次就是三次下载量
