我在 GKE 上有一个 Kubernetes 集群。我知道 Kubernetes 会传播具有相同标签的 pod，但这不会发生在我身上。这是我的节点描述。
Name: gke-pubnation-cluster-prod-high-cpu-14a766ad-node-dpob
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
OutOfDisk False Fri, 27 May 2016 21:11:17 -0400 Thu, 26 May 2016 22:16:27 -0400 KubeletHasSufficientDisk kubelet has sufficient disk space available
Ready True Fri, 27 May 2016 21:11:17 -0400 Thu, 26 May 2016 22:17:02 -0400 KubeletReady kubelet is posting ready status. WARNING: CPU hardcapping unsupported
Capacity:
cpu: 2
memory: 1848660Ki
pods: 110
System Info:
Machine ID:
Kernel Version: 3.16.0-4-amd64
OS Image: Debian GNU/Linux 7 (wheezy)
Container Runtime Version: docker://1.9.1
Kubelet Version: v1.2.4
Kube-Proxy Version: v1.2.4
Non-terminated Pods: (2 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits
--------- ---- ------------ ---------- --------------- -------------
kube-system fluentd-cloud-logging-gke-pubnation-cluster-prod-high-cpu-14a766ad-node-dpob 80m (4%) 0 (0%) 200Mi (11%) 200Mi (11%)
kube-system kube-proxy-gke-pubnation-cluster-prod-high-cpu-14a766ad-node-dpob 20m (1%) 0 (0%) 0 (0%) 0 (0%)
Allocated resources:
(Total limits may be over 100%, i.e., overcommitted. More info: http://releases.k8s.io/HEAD/docs/user-guide/compute-resources.md)
CPU Requests CPU Limits Memory Requests Memory Limits
------------ ---------- --------------- -------------
100m (5%) 0 (0%) 200Mi (11%) 200Mi (11%)
No events.
Name: gke-pubnation-cluster-prod-high-cpu-14a766ad-node-qhw2
Conditions:
Type Status LastHeartbeatTime LastTransitionTime Reason Message
---- ------ ----------------- ------------------ ------ -------
OutOfDisk False Fri, 27 May 2016 21:11:17 -0400 Fri, 27 May 2016 18:16:38 -0400 KubeletHasSufficientDisk kubelet has sufficient disk space available
Ready True Fri, 27 May 2016 21:11:17 -0400 Fri, 27 May 2016 18:17:12 -0400 KubeletReady kubelet is posting ready status. WARNING: CPU hardcapping unsupported
Capacity:
pods: 110
cpu: 2
memory: 1848660Ki
System Info:
Machine ID:
Kernel Version: 3.16.0-4-amd64
OS Image: Debian GNU/Linux 7 (wheezy)
Container Runtime Version: docker://1.9.1
Kubelet Version: v1.2.4
Kube-Proxy Version: v1.2.4
Non-terminated Pods: (10 in total)
Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits
--------- ---- ------------ ---------- --------------- -------------
default pn-minions-deployment-prod-3923308490-axucq 100m (5%) 0 (0%) 0 (0%) 0 (0%)
default pn-minions-deployment-prod-3923308490-mvn54 100m (5%) 0 (0%) 0 (0%) 0 (0%)
default pn-minions-deployment-staging-2522417973-8cq5p 100m (5%) 0 (0%) 0 (0%) 0 (0%)
default pn-minions-deployment-staging-2522417973-9yatt 100m (5%) 0 (0%) 0 (0%) 0 (0%)
kube-system fluentd-cloud-logging-gke-pubnation-cluster-prod-high-cpu-14a766ad-node-qhw2 80m (4%) 0 (0%) 200Mi (11%) 200Mi (11%)
kube-system heapster-v1.0.2-1246684275-a8eab 150m (7%) 150m (7%) 308Mi (17%) 308Mi (17%)
kube-system kube-dns-v11-uzl1h 310m (15%) 310m (15%) 170Mi (9%) 920Mi (50%)
kube-system kube-proxy-gke-pubnation-cluster-prod-high-cpu-14a766ad-node-qhw2 20m (1%) 0 (0%) 0 (0%) 0 (0%)
kube-system kubernetes-dashboard-v1.0.1-3co2b 100m (5%) 100m (5%) 50Mi (2%) 50Mi (2%)
kube-system l7-lb-controller-v0.6.0-o5ojv 110m (5%) 110m (5%) 70Mi (3%) 120Mi (6%)
Allocated resources:
(Total limits may be over 100%, i.e., overcommitted. More info: http://releases.k8s.io/HEAD/docs/user-guide/compute-resources.md)
CPU Requests CPU Limits Memory Requests Memory Limits
------------ ---------- --------------- -------------
1170m (58%) 670m (33%) 798Mi (44%) 1598Mi (88%)
No events.
这里是部署的描述:
Name: pn-minions-deployment-prod
Namespace: default
Labels: app=pn-minions,environment=production
Selector: app=pn-minions,environment=production
Replicas: 2 updated | 2 total | 2 available | 0 unavailable
OldReplicaSets: <none>
NewReplicaSet: pn-minions-deployment-prod-3923308490 (2/2 replicas created)
Name: pn-minions-deployment-staging
Namespace: default
Labels: app=pn-minions,environment=staging
Selector: app=pn-minions,environment=staging
Replicas: 2 updated | 2 total | 2 available | 0 unavailable
OldReplicaSets: <none>
NewReplicaSet: pn-minions-deployment-staging-2522417973 (2/2 replicas created)
如您所见，所有四个 pod 都在同一个节点上。我是否应该做一些额外的事情来完成这项工作？
最佳答案
默认情况下，pod 以不受限制的 CPU 和内存限制运行。这意味着系统中的任何 pod 都能够在执行该 pod 的节点上消耗尽可能多的 CPU 和内存。 http://kubernetes.io/docs/admin/limitrange/
当您不指定 CPU 限制时，kubernetes 将不知道需要多少 CPU 资源，并会尝试在一个节点中创建 pod。
这是一个部署
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: jenkins
spec:
replicas: 4
template:
metadata:
labels:
app: jenkins
spec:
containers:
- name: jenkins
image: quay.io/naveensrinivasan/jenkins:0.4
ports:
- containerPort: 8080
resources:
limits:
cpu: "400m"
# volumeMounts:
# - mountPath: /var/jenkins_home
# name: jenkins-volume
# volumes:
# - name: jenkins-volume
# awsElasticBlockStore:
# volumeID: vol-29c4b99f
# fsType: ext4
imagePullSecrets:
- name: registrypullsecret
这是 kubectl describe po | 的输出grep Node 创建部署后。
~ aws_kubernetes naveen@GuessWho ~/revature/devops/jenkins jenkins ● k describe po | grep Node
Node: ip-172-20-0-26.us-west-2.compute.internal/172.20.0.26
Node: ip-172-20-0-29.us-west-2.compute.internal/172.20.0.29
Node: ip-172-20-0-27.us-west-2.compute.internal/172.20.0.27
Node: ip-172-20-0-29.us-west-2.compute.internal/172.20.0.29
它现在在 4 个不同的节点中创建。它基于集群上的 CPU 限制。您可以增加/减少 replicas 以查看它被部署在不同的节点中。
这不是特定于 GKE 或 AWS 的。
关于Kubernetes pod 没有分布在不同的节点上，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37494314/