K8S故障处理：coredns状态异常处理记录(2)

K8S故障处理

这个报错比较明显，解决方式同场景一

3. 服务器重启后coredns异常

coredns部署后状态在CrashLoopBackOff和Error不停转换

[root@02-3 ~]# kubectl  get pods -owide -n  kube-system
NAME                                  READY   STATUS             RESTARTS   AGE    IP             NODE           NOMINATED NODE   READINESS GATES
coredns-5mftn                         1/1     Running            2          174d   172.27.0.214   10.10.28.10    <none>           <none>
coredns-9bnl8                         1/1     Running            2          62d    172.27.4.31    10.10.28.141   <none>           <none>
coredns-n2knx                         0/1     CrashLoopBackOff   2          37s    172.27.2.167   10.10.28.116   <none>           <none>

查看coredns的pod日志

[root@02-3 ~]# kubectl describe pods coredns-n2knx   -n kube-system
.....
Events:
  Type     Reason     Age                  From               Message
  ----     ------     ----                 ----               -------
  Normal   Scheduled  2m4s                 default-scheduler  Successfully assigned kube-system/coredns-n2knx to 10.10.28.116
  Warning  BackOff    31s (x10 over 2m1s)  kubelet            Back-off restarting failed container
  Normal   Pulled     17s (x5 over 2m4s)   kubelet            Container image "reg.wps.lan:5000/wps/coredns:1.8.3" already present on machine
  Normal   Created    17s (x5 over 2m4s)   kubelet            Created container coredns
  Normal   Started    17s (x5 over 2m3s)   kubelet            Started container coredns

从日志上看到coredns无法启动，直接查看docker的日志

[root@02-3 ~]# docker ps -a | grep coredns
d8bfd8b06015   3885a5b7f138                                   "/coredns -conf /etc…"   26 seconds ago   Exited (1) 25 seconds ago             k8s_coredns_coredns-n2knx_kube-system_a78e5c88-6776-4a4e-ab48-d380b0f18c93_4
e7368c926cb0   reg.wps.lan:5000/wps/pause:3.3                 "/pause"                 2 minutes ago    Up 2 minutes                          k8s_POD_coredns-n2knx_kube-system_a78e5c88-6776-4a4e-ab48-d380b0f18c93_0
[root@02-3 ~]# 
[root@02-3 ~]# docker logs -f d8bfd8b06015
.:53
[INFO] plugin/reload: Running configuration MD5 = 4fe39d48e613d0d0369935d7aafb5fa6
CoreDNS-1.8.3
linux/amd64, go1.16, 4293992
[FATAL] plugin/loop: Loop (127.0.0.1:59055 -> :53) detected for zone ".", see https://coredns.io/plugins/loop#troubleshooting. Query: "HINFO 184772892781744701.6546771560531965938."

检查dns配置，nameserver的dns配置成了127.0.0.1，修改成正确的dns地址即可

[root@02-3 ~]# cat /etc/resolv.conf 
; generated by /usr/sbin/dhclient-script
search openstacklocal novalocal
nameserver 127.0.0.1

以上就是IT袋网带来的K8S故障处理 以及 coredns状态异常处理记录的详细内容了，IT袋网网希望能给您带来帮助！