我有一个Pod正在运行，并且想向前移植，以便可以从内部网络访问Pod。 我不知道它正在监听哪个端口，尚无服务。
我描述了吊舱：
$ kubectl describe pod queue-l7wck
Name: queue-l7wck
Namespace: default
Priority: 0
Node: minikube/192.168.64.3
Start Time: Wed, 18 Dec 2019 05:13:56 +0200
Labels: app=work-queue
chapter=jobs
component=queue
Annotations: <none>
Status: Running
IP: 172.17.0.2
IPs:
IP: 172.17.0.2
Controlled By: ReplicaSet/queue
Containers:
queue:
Container ID: docker://13780475170fa2c0d8e616ba1a3b1554d31f404cc0a597877e790cbf01838e63
Image: gcr.io/kuar-demo/kuard-amd64:blue
Image ID: docker-pullable://gcr.io/kuar-demo/kuard-amd64@sha256:1ecc9fb2c871302fdb57a25e0c076311b7b352b0a9246d442940ca8fb4efe229
Port: <none>
Host Port: <none>
State: Running
Started: Wed, 18 Dec 2019 05:14:02 +0200
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-mbn5b (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
default-token-mbn5b:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-mbn5b
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled <unknown> default-scheduler Successfully assigned default/queue-l7wck to minikube
Normal Pulling 31h kubelet, minikube Pulling image "gcr.io/kuar-demo/kuard-amd64:blue"
Normal Pulled 31h kubelet, minikube Successfully pulled image "gcr.io/kuar-demo/kuard-amd64:blue"
Normal Created 31h kubelet, minikube Created container queue
Normal Started 31h kubelet, minikube Started container queue
即使JSON也没有任何内容：
$ kubectl get pods queue-l7wck -o json
{
"apiVersion": "v1",
"kind": "Pod",
"metadata": {
"creationTimestamp": "2019-12-18T03:13:56Z",
"generateName": "queue-",
"labels": {
"app": "work-queue",
"chapter": "jobs",
"component": "queue"
},
"name": "queue-l7wck",
"namespace": "default",
"ownerReferences": [
{
"apiVersion": "apps/v1",
"blockOwnerDeletion": true,
"controller": true,
"kind": "ReplicaSet",
"name": "queue",
"uid": "a9ec07f7-07a3-4462-9ac4-a72226f54556"
}
],
"resourceVersion": "375402",
"selfLink": "/api/v1/namespaces/default/pods/queue-l7wck",
"uid": "af43027d-8377-4227-b366-bcd4940b8709"
},
"spec": {
"containers": [
{
"image": "gcr.io/kuar-demo/kuard-amd64:blue",
"imagePullPolicy": "Always",
"name": "queue",
"resources": {},
"terminationMessagePath": "/dev/termination-log",
"terminationMessagePolicy": "File",
"volumeMounts": [
{
"mountPath": "/var/run/secrets/kubernetes.io/serviceaccount",
"name": "default-token-mbn5b",
"readOnly": true
}
]
}
],
"dnsPolicy": "ClusterFirst",
"enableServiceLinks": true,
"nodeName": "minikube",
"priority": 0,
"restartPolicy": "Always",
"schedulerName": "default-scheduler",
"securityContext": {},
"serviceAccount": "default",
"serviceAccountName": "default",
"terminationGracePeriodSeconds": 30,
"tolerations": [
{
"effect": "NoExecute",
"key": "node.kubernetes.io/not-ready",
"operator": "Exists",
"tolerationSeconds": 300
},
{
"effect": "NoExecute",
"key": "node.kubernetes.io/unreachable",
"operator": "Exists",
"tolerationSeconds": 300
}
],
"volumes": [
{
"name": "default-token-mbn5b",
"secret": {
"defaultMode": 420,
"secretName": "default-token-mbn5b"
}
}
]
},
"status": {
"conditions": [
{
"lastProbeTime": null,
"lastTransitionTime": "2019-12-18T03:13:56Z",
"status": "True",
"type": "Initialized"
},
{
"lastProbeTime": null,
"lastTransitionTime": "2019-12-18T03:14:02Z",
"status": "True",
"type": "Ready"
},
{
"lastProbeTime": null,
"lastTransitionTime": "2019-12-18T03:14:02Z",
"status": "True",
"type": "ContainersReady"
},
{
"lastProbeTime": null,
"lastTransitionTime": "2019-12-18T03:13:56Z",
"status": "True",
"type": "PodScheduled"
}
],
"containerStatuses": [
{
"containerID": "docker://13780475170fa2c0d8e616ba1a3b1554d31f404cc0a597877e790cbf01838e63",
"image": "gcr.io/kuar-demo/kuard-amd64:blue",
"imageID": "docker-pullable://gcr.io/kuar-demo/kuard-amd64@sha256:1ecc9fb2c871302fdb57a25e0c076311b7b352b0a9246d442940ca8fb4efe229",
"lastState": {},
"name": "queue",
"ready": true,
"restartCount": 0,
"started": true,
"state": {
"running": {
"startedAt": "2019-12-18T03:14:02Z"
}
}
}
],
"hostIP": "192.168.64.3",
"phase": "Running",
"podIP": "172.17.0.2",
"podIPs": [
{
"ip": "172.17.0.2"
}
],
"qosClass": "BestEffort",
"startTime": "2019-12-18T03:13:56Z"
}
}
如何检查Kubectl在Pod侦听的端口？
更新
如果我缩进吊舱并按照评论中的建议运行netstat -tulpn，则会得到：
$ kubectl exec -it queue-pfmq2 -- sh
~ $ netstat -tulpn
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 :::8080 :::* LISTEN 1/kuard
但是此方法未使用kubectl。
答案 0 :(得分：3)
尝试结合 kubectl 和您的 Linux 命令以获取正在侦听的 端口 容器：
kubectl exec <pod name here> -- netstat -tulpn
此外，如果需要，您可以使用 grep 将此结果通过管道缩小范围，例如。
kubectl exec <pod name here> -- netstat -tulpn | grep "search string"
注意：只有当您的容器的基本映像支持命令 netstat 时，它才会起作用。根据您的更新部分，它似乎支持。
上面的解决方案只不过是巧妙地使用了您在两部分中使用的命令，首先在交互模式下exec 容器，在容器中使用 -it 第二个列出侦听端口。
答案 1 :(得分：1)
您的容器映像在构建期间使用EXPOSE command in the Dockerfile打开了一个端口（在您的情况下，看起来像8080端口）。由于裸露的端口已烘焙到图像中，因此k8s无需跟踪此打开的端口，因为k8s无需采取步骤即可将其打开。
由于k8s不负责打开端口，因此您将无法使用kubectl或检查Pod YAML找到监听端口
答案 2 :(得分：0)
通常。一个容器将能够运行 curl 。所以你可以使用 curl 来检查端口是否打开。
for port in 8080 50000 443 8443;do curl -I - connect-timeout 1 127.0.0.1:$port;done
这可以用 sh 运行。