microk8s coredns CrashLoopBackOff

Question

我在 Ubuntu 上使用 microk8s，但是 coredns pod 無法啟動，我懷疑這給了我其他 pod 問題。

Pod 在運行 get pods 時顯示 CrashLoopBackOff 狀態

這是 pod 的描述：

Name:                 coredns-86f78bb79c-bdt7t
Namespace:            kube-system
Priority:             2000000000
Priority Class Name:  system-cluster-critical
Node:                 chwc21ubtu/10.2.2.10
Start Time:           Tue, 25 Jan 2022 09:35:45 +0000
Labels:               k8s-app=kube-dns
                      pod-template-hash=86f78bb79c
Annotations:          cni.projectcalico.org/podIP: 10.1.249.135/32
                      cni.projectcalico.org/podIPs: 10.1.249.135/32
                      scheduler.alpha.kubernetes.io/critical-pod:
Status:               Running
IP:                   10.1.249.135
IPs:
  IP:           10.1.249.135
Controlled By:  ReplicaSet/coredns-86f78bb79c
Containers:
  coredns:
    Container ID:  containerd://045a0cdd5d6e1b736f9f7469a189cbbc2c87df56c2af62bcdc825eda0aa3719c
    Image:         coredns/coredns:1.6.6
    Image ID:      docker.io/coredns/coredns@sha256:41bee6992c2ed0f4628fcef75751048927bcd6b1cee89c79f6acb63ca5474d5a
    Ports:         53/UDP, 53/TCP, 9153/TCP
    Host Ports:    0/UDP, 0/TCP, 0/TCP
    Args:
      -conf
      /etc/coredns/Corefile
    State:          Waiting
      Reason:       CrashLoopBackOff
    Last State:     Terminated
      Reason:       Error
      Exit Code:    1
      Started:      Tue, 25 Jan 2022 11:54:55 +0000
      Finished:     Tue, 25 Jan 2022 11:54:55 +0000
    Ready:          False
    Restart Count:  32
    Limits:
      memory:  170Mi
    Requests:
      cpu:        100m
      memory:     70Mi
    Liveness:     http-get http://:8080/health delay=60s timeout=5s period=10s #success=1 #failure=5
    Readiness:    http-get http://:8181/ready delay=0s timeout=1s period=10s #success=1 #failure=3
    Environment:  <none>
    Mounts:
      /etc/coredns from config-volume (ro)
      /var/run/secrets/kubernetes.io/serviceaccount from coredns-token-rj6x7 (ro)
Conditions:
  Type              Status
  Initialized       True
  Ready             False
  ContainersReady   False
  PodScheduled      True
Volumes:
  config-volume:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      coredns
    Optional:  false
  coredns-token-rj6x7:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  coredns-token-rj6x7
    Optional:    false
QoS Class:       Burstable
Node-Selectors:  <none>
Tolerations:     CriticalAddonsOnly op=Exists
                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                 node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type     Reason   Age                     From     Message
  ----     ------   ----                    ----     -------
  Warning  BackOff  3m56s (x663 over 143m)  kubelet  Back-off restarting failed container

以下是 /etc/resolv/conf 的內容：

cat /etc/resolv.conf
# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients to the
# internal DNS stub resolver of systemd-resolved. This file lists all
# configured search domains.
#
# Run "resolvectl status" to see details about the uplink DNS servers
# currently in use.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 127.0.0.53
options edns0 trust-ad
search wnzgl0qq22vevmrhjm1h5bny0c.zx.internal.cloudapp.net

以下是日志的內容：

sudo microk8s.kubectl -n kube-system logs -p coredns-86f78bb79c-bdt7t
plugin/forward: not an IP address or file: "reload"

查看 coreDNS 的配置映射，似乎有一個名為“reload”的額外值被歸類為 IP 轉發/文件

# 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: v1
data:
  Corefile: |
    .:53 {
        errors
        health {
          lameduck 5s
        }
        ready
        log . {
          class error
        }
        kubernetes cluster.local in-addr.arpa ip6.arpa {
          pods insecure
          fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . 8.8.8.8 8.8.4.4    reload
        loadbalance
    }
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"Corefile":".:53 {\n    errors\n    health {\n      lameduck 5s\n    }\n    ready\n    log . {\n      class error\n    }\n    kubernetes cluster.local in-addr.arpa ip6.arpa {\n      pods insecure\n      fallthrough in-addr.arpa ip6.arpa\n    }\n    prometheus :9153\n    forward . 8.8.8.8 8.8.4.4    reload\n    loadbalance\n}\n"},"kind":"ConfigMap","metadata":{"annotations":{},"creationTimestamp":"2022-01-25T09:35:32Z","labels":{"addonmanager.kubernetes.io/mode":"EnsureExists","k8s-app":"kube-dns"},"managedFields":[{"apiVersion":"v1","fieldsType":"FieldsV1","fieldsV1":{"f:data":{".":{},"f:Corefile":{}},"f:metadata":{"f:annotations":{".":{},"f:kubectl.kubernetes.io/last-applied-configuration":{}},"f:labels":{".":{},"f:addonmanager.kubernetes.io/mode":{},"f:k8s-app":{}}}},"manager":"kubectl-client-side-apply","operation":"Update","time":"2022-01-25T09:35:32Z"}],"name":"coredns","namespace":"kube-system","resourceVersion":"518","selfLink":"/api/v1/namespaces/kube-system/configmaps/coredns","uid":"8a73848a-4118-417b-80f5-2175bb64acc4"}}
  creationTimestamp: "2022-01-25T09:35:32Z"
  labels:
    addonmanager.kubernetes.io/mode: EnsureExists
    k8s-app: kube-dns
  name: coredns
  namespace: kube-system
  resourceVersion: "597"
  selfLink: /api/v1/namespaces/kube-system/configmaps/coredns
  uid: 8a73848a-4118-417b-80f5-2175bb64acc4

我不知道下一步該往哪里看 - 任何人都可以提供任何建議嗎？

Answer 1

退出代碼1表示應用程序錯誤。

檢查此鏈接以獲取有關退出代碼的更多信息。

Answer 2

解決！

在配置 map 中，在“重新加載”一詞之前應該有一個carrage return。 我使用以下命令和 vim 修改了配置 map；

我的配置 map 現在看起來像這樣

# 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: v1
data:
  Corefile: |
    .:53 {
        errors
        health {
          lameduck 5s
        }
        ready
        log . {
          class error
        }
        kubernetes cluster.local in-addr.arpa ip6.arpa {
          pods insecure
          fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . 8.8.8.8 8.8.4.4
        reload
        loadbalance
    }
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"Corefile":".:53 {\n    errors\n    health {\n      lameduck 5s\n    }\n    ready\n    log . {\n      class error\n    }\n    kubernetes cluster.local in-addr.arpa ip6.arpa {\n      pods insecure\n      fallthrough in-addr.arpa ip6.arpa\n    }\n    prometheus :9153\n    forward . 8.8.8.8 8.8.4.4    **reload**\n    loadbalance\n}\n"},"kind":"ConfigMap","metadata":{"annotations":{},"creationTimestamp":"2022-01-25T09:35:32Z","labels":{"addonmanager.kubernetes.io/mode":"EnsureExists","k8s-app":"kube-dns"},"managedFields":[{"apiVersion":"v1","fieldsType":"FieldsV1","fieldsV1":{"f:data":{".":{},"f:Corefile":{}},"f:metadata":{"f:annotations":{".":{},"f:kubectl.kubernetes.io/last-applied-configuration":{}},"f:labels":{".":{},"f:addonmanager.kubernetes.io/mode":{},"f:k8s-app":{}}}},"manager":"kubectl-client-side-apply","operation":"Update","time":"2022-01-25T09:35:32Z"}],"name":"coredns","namespace":"kube-system","resourceVersion":"518","selfLink":"/api/v1/namespaces/kube-system/configmaps/coredns","uid":"8a73848a-4118-417b-80f5-2175bb64acc4"}}
  creationTimestamp: "2022-01-25T09:35:32Z"
  labels:
    addonmanager.kubernetes.io/mode: EnsureExists
    k8s-app: kube-dns
  name: coredns
  namespace: kube-system
  resourceVersion: "18764"
  selfLink: /api/v1/namespaces/kube-system/configmaps/coredns
  uid: 8a73848a-4118-417b-80f5-2175bb64acc4
~                                                                                                                                                            ~                                                                                                                                                            ~                                                                                                                                                            ~                                             

sudo microk8s.kubectl -n kube-system edit configmaps coredns -o yaml

然后我使用重新啟動了所有 pod

sudo microk8s.kubectl -n kube-system rollout restart deploy