查看daemonset
如下，k8s自身的 DaemonSet kube-flannel-ds和kube-proxy分别负责在每个结点上运行flannel和kube-proxy组件
daemonset在每个节点上最多只能运行一个副本。
[machangwei@mcwk8s-master ~]$ kubectl get daemonset No resources found in default namespace. [machangwei@mcwk8s-master ~]$ kubectl get daemonset --namespace=kube-system NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE kube-flannel-ds 3 3 1 3 1 <none> 5d kube-proxy 3 3 3 3 3 kubernetes.io/os=linux 5d [machangwei@mcwk8s-master ~]$ kubectl get pod --namespace=kube-system -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES coredns-6d8c4cb4d-cnj2t 1/1 Running 0 5d 10.244.0.2 mcwk8s-master <none> <none> coredns-6d8c4cb4d-ngfm4 1/1 Running 0 5d 10.244.0.3 mcwk8s-master <none> <none> etcd-mcwk8s-master 1/1 Running 0 5d 10.0.0.4 mcwk8s-master <none> <none> kube-apiserver-mcwk8s-master 1/1 Running 1 (13h ago) 5d 10.0.0.4 mcwk8s-master <none> <none> kube-controller-manager-mcwk8s-master 1/1 Running 5 (80m ago) 5d 10.0.0.4 mcwk8s-master <none> <none> kube-flannel-ds-cn4m9 0/1 CrashLoopBackOff 147 (3m51s ago) 12h 10.0.0.6 mcwk8s-node2 <none> <none> kube-flannel-ds-hpgkz 1/1 Running 0 5d 10.0.0.4 mcwk8s-master <none> <none> kube-flannel-ds-nnjvj 0/1 CrashLoopBackOff 185 (3m38s ago) 5d 10.0.0.5 mcwk8s-node1 <none> <none> kube-proxy-92g5c 1/1 Running 0 12h 10.0.0.6 mcwk8s-node2 <none> <none> kube-proxy-kk22j 1/1 Running 0 5d 172.16.0.5 mcwk8s-node1 <none> <none> kube-proxy-xjjgf 1/1 Running 0 5d 10.0.0.4 mcwk8s-master <none> <none> kube-scheduler-mcwk8s-master 1/1 Running 5 (82m ago) 5d 10.0.0.4 mcwk8s-master <none> <none> [machangwei@mcwk8s-master ~]$
学习kube-flannel-ds
截取部分：https://www.cnblogs.com/machangwei-8/p/15759077.html#_label7
apiVersion: apps/v1
kind: DaemonSet #语法结构和Deployment几乎往前一样，只是将kind设为DaemonSet
metadata:
name: kube-flannel-ds
namespace: kube-system
labels:
tier: node
app: flannel
spec:
selector:
matchLabels:
app: flannel
template:
metadata:
labels:
tier: node
app: flannel
spec:
hostNetwork: true #指定Pod直接使用的是Node网络，相当于docker run --network=host。
#考虑到flannel需要为集群提供网络连接，这个要求是合理的
initContainers:#定义了运行flannel服务的两个容器
- name: install-cni-plugin
image: rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.0
command:
containers: #定义了运行flannel服务的两个容器
- name: kube-flannel
image: quay.io/coreos/flannel:v0.15.1
command:
- /opt/bin/flanneld
args:
- --ip-masq
- --kube-subnet-mgr
学习kube-proxy,查看daemonset配置
[machangwei@mcwk8s-master ~]$ kubectl edit daemonset kube-proxy --namespace=kube-system
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: apps/v1
kind: DaemonSet #指定资源类型
metadata:
annotations:
deprecated.daemonset.template.generation: "1"
creationTimestamp: "2022-01-12T15:15:18Z"
generation: 1
labels:
k8s-app: kube-proxy
name: kube-proxy
namespace: kube-system
resourceVersion: "18274"
uid: 04cfea8d-94b3-4963-b8d2-b10a7b6a46b0
spec:
revisionHistoryLimit: 10
selector:
matchLabels:
k8s-app: kube-proxy
template:
metadata:
creationTimestamp: null
labels:
k8s-app: kube-proxy
spec:
containers:
- command:
- /usr/local/bin/kube-proxy
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: apps/v1
kind: DaemonSet #指定资源类型
metadata:
annotations:
deprecated.daemonset.template.generation: "1"
creationTimestamp: "2022-01-12T15:15:18Z"
generation: 1
labels:
k8s-app: kube-proxy
name: kube-proxy
namespace: kube-system
resourceVersion: "18274"
uid: 04cfea8d-94b3-4963-b8d2-b10a7b6a46b0
spec:
revisionHistoryLimit: 10
selector:
matchLabels:
k8s-app: kube-proxy
template:
metadata:
creationTimestamp: null
labels:
k8s-app: kube-proxy
spec:
containers: #定义kube-proxy的容器
- command:
- /usr/local/bin/kube-proxy
- --config=/var/lib/kube-proxy/config.conf
- --hostname-override=$(NODE_NAME)
env:
- name: NODE_NAME
valueFrom:
fieldRef:
apiVersion: v1
fieldPath: spec.nodeName
image: registry.aliyuncs.com/google_containers/kube-proxy:v1.23.1
imagePullPolicy: IfNotPresent
name: kube-proxy
resources: {}
securityContext:
privileged: true
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
volumeMounts:
- mountPath: /var/lib/kube-proxy
name: kube-proxy
- mountPath: /run/xtables.lock
name: xtables-lock
- mountPath: /lib/modules
name: lib-modules
readOnly: true
dnsPolicy: ClusterFirst
hostNetwork: true
nodeSelector:
kubernetes.io/os: linux
priorityClassName: system-node-critical
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
serviceAccount: kube-proxy
serviceAccountName: kube-proxy
terminationGracePeriodSeconds: 30
tolerations:
- operator: Exists
volumes:
- configMap:
defaultMode: 420
name: kube-proxy
name: kube-proxy
- hostPath:
path: /run/xtables.lock
type: FileOrCreate
name: xtables-lock
- hostPath:
path: /lib/modules
type: ""
name: lib-modules
updateStrategy:
rollingUpdate:
maxSurge: 0
maxUnavailable: 1
type: RollingUpdate
status: #当前DamonSet的运行状态，这个部分是kubectl edit 特有的。其实kubernetes集群中每个当前运行的资源都
currentNumberScheduled: 3 #可以通过kubectl edit 查看器配置和运行状态，
desiredNumberScheduled: 3 #比如： kubectl edit deployment mcwnginx-deployment
numberAvailable: 3
numberMisscheduled: 0
numberReady: 3
observedGeneration: 1
updatedNumberScheduled: 3
[machangwei@mcwk8s-master ~]$ kubectl edit daemonset kube-proxy --namespace=kube-system #跟vim一样，q退出，如果修改了那么应该是wq吧
Edit cancelled, no changes made.
运行自己的DaemonSet失败
有时间再看这个失败问题，如果哪位大佬知道，指点下也好
[machangwei@mcwk8s-master ~]$ vim mcwJiankong.yml
[machangwei@mcwk8s-master ~]$ cat mcw
cat: mcw: No such file or directory
[machangwei@mcwk8s-master ~]$ cat mcw
mcwJiankong.yml mcwNginx.yml
[machangwei@mcwk8s-master ~]$ cat mcwJiankong.yml
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: mcw-prometheus-node-daemonset
spec:
replicas: 3
selector:
matchLabels:
app: mcw_prometheus
template:
metadata:
labels:
app: mcw_prometheus
spec:
hostNetwork: true
containers:
- name: mcw-pr-node
image: prom/node-exporter
imagePullPolicy: IfNotPresent
command:
- /bin/node_exporter
- --pathprocfs
- /host/proc
- --path.sysfs
- /host/sys
- --collector.filesystem.ignored-mount-points
- ^/(sys|proc|dev|host|etc)($|/)
volumeMounts:
- name: proc
mountPath: /host/proc
- name: sys
mountPath: /host/sys
- name: root
mountPath: /rootfs
volumes:
- name: proc
hostPath:
path: /proc
- name: sys
hostPath:
path: /sys
- name: root
hostPath:
path: /
[machangwei@mcwk8s-master ~]$ kubectl apply -f mcwJiankong.yml #daemonset不能指定副本数量，好像每个节点都会运行，这里可能没包括主节点
error: error validating "mcwJiankong.yml": error validating data: ValidationError(DaemonSet.spec): unknown field "replicas" in io.k8s.api.apps.v1.DaemonSetSpec; if you choose to ignore these errors, turn validation off with --validate=false
[machangwei@mcwk8s-master ~]$
[machangwei@mcwk8s-master ~]$ vim mcwJiankong.yml
[machangwei@mcwk8s-master ~]$ cat mcwJiankong.yml #去掉副本数
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: mcw-prometheus-node-daemonset
spec:
selector:
matchLabels:
app: mcw_prometheus
template:
metadata:
labels:
app: mcw_prometheus
spec:
hostNetwork: true
containers:
- name: mcw-pr-node
image: prom/node-exporter
imagePullPolicy: IfNotPresent
command:
- /bin/node_exporter
- --pathprocfs
- /host/proc
- --path.sysfs
- /host/sys
- --collector.filesystem.ignored-mount-points
- ^/(sys|proc|dev|host|etc)($|/)
volumeMounts:
- name: proc
mountPath: /host/proc
- name: sys
mountPath: /host/sys
- name: root
mountPath: /rootfs
volumes:
- name: proc
hostPath:
path: /proc
- name: sys
hostPath:
path: /sys
- name: root
hostPath:
path: /
[machangwei@mcwk8s-master ~]$
[machangwei@mcwk8s-master ~]$
[machangwei@mcwk8s-master ~]$ kubectl apply -f mcwJiankong.yml
daemonset.apps/mcw-prometheus-node-daemonset created
[machangwei@mcwk8s-master ~]$ kubectl get daemonset #查看daemonset
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE
mcw-prometheus-node-daemonset 2 2 0 2 0 <none> 19s
[machangwei@mcwk8s-master ~]$ kubectl get pod -o wide #查看pod，结果未能成功运行。不清楚原因，有时间再看这个问题
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
mcw-prometheus-node-daemonset-cv8k2 0/1 CrashLoopBackOff 2 (17s ago) 60s 10.0.0.5 mcwk8s-node1 <none> <none>
mcw-prometheus-node-daemonset-z2vvc 0/1 Error 2 (30s ago) 60s 10.0.0.6 mcwk8s-node2 <none> <none>
[machangwei@mcwk8s-master ~]$ kubectl describe pod mcw-prometheus-node-daemonset-cv8k2
Name: mcw-prometheus-node-daemonset-cv8k2
Namespace: default
Priority: 0
Node: mcwk8s-node1/10.0.0.5
Start Time: Tue, 18 Jan 2022 00:34:32 +0800
Labels: app=mcw_prometheus
controller-revision-hash=7b99d77578
pod-template-generation=1
Annotations: <none>
Status: Running
IP: 10.0.0.5
IPs:
IP: 10.0.0.5
Controlled By: DaemonSet/mcw-prometheus-node-daemonset
Containers:
mcw-pr-node:
Container ID: docker://7ff049b0c303ebb997c4794c9ffadbe7520f8cfdba71caec3b6b32c193ea1369
Image: prom/node-exporter
Image ID: docker-pullable://prom/node-exporter@sha256:f2269e73124dd0f60a7d19a2ce1264d33d08a985aed0ee6b0b89d0be470592cd
Port: <none>
Host Port: <none>
Command:
/bin/node_exporter
--pathprocfs
/host/proc
--path.sysfs
/host/sys
--collector.filesystem.ignored-mount-points
^/(sys|proc|dev|host|etc)($|/)
State: Waiting
Reason: CrashLoopBackOff
Last State: Terminated
Reason: Error
Exit Code: 1
Started: Tue, 18 Jan 2022 00:36:24 +0800
Finished: Tue, 18 Jan 2022 00:36:24 +0800
Ready: False
Restart Count: 4
Environment: <none>
Mounts:
/host/proc from proc (rw)
/host/sys from sys (rw)
/rootfs from root (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-w9bkl (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
proc:
Type: HostPath (bare host directory volume)
Path: /proc
HostPathType:
sys:
Type: HostPath (bare host directory volume)
Path: /sys
HostPathType:
root:
Type: HostPath (bare host directory volume)
Path: /
HostPathType:
kube-api-access-w9bkl:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/disk-pressure:NoSchedule op=Exists
node.kubernetes.io/memory-pressure:NoSchedule op=Exists
node.kubernetes.io/network-unavailable:NoSchedule op=Exists
node.kubernetes.io/not-ready:NoExecute op=Exists
node.kubernetes.io/pid-pressure:NoSchedule op=Exists
node.kubernetes.io/unreachable:NoExecute op=Exists
node.kubernetes.io/unschedulable:NoSchedule op=Exists
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 2m36s default-scheduler Successfully assigned default/mcw-prometheus-node-daemonset-cv8k2 to mcwk8s-node1
Normal Pulling 2m36s kubelet Pulling image "prom/node-exporter"
Normal Pulled 2m9s kubelet Successfully pulled image "prom/node-exporter" in 27.526626918s
Normal Created 45s (x5 over 2m9s) kubelet Created container mcw-pr-node
Normal Started 45s (x5 over 2m8s) kubelet Started container mcw-pr-node
Normal Pulled 45s (x4 over 2m8s) kubelet Container image "prom/node-exporter" already present on machine
Warning BackOff 31s (x9 over 2m7s) kubelet Back-off restarting failed container
[machangwei@mcwk8s-master ~]$