CoreDNS is not working after installation of microk8s

[kalena]

I have installed a microk8s on my 64 bit raspbian, and enabled a dns server by

microk8s enable dns

Coredns is continously cashes:

microk8s.kubectl describe pod coredns-64c6478b6c-snkxx --namespace=kube-system
Namespace:            kube-system

Priority:             2000000000

Priority Class Name:  system-cluster-critical

Node:                 raspberrypi4-docker3/192.168.0.129

Start Time:           Fri, 12 Aug 2022 18:28:54 +0200

Labels:               k8s-app=kube-dns

pod-template-hash=64c6478b6c

Annotations:          cni.projectcalico.org/podIP: 10.1.174.245/32

cni.projectcalico.org/podIPs: 10.1.174.245/32

priorityClassName: system-cluster-critical

Status:               Running

IP:                   10.1.174.245

IPs:

IP:           10.1.174.245

Controlled By:  ReplicaSet/coredns-64c6478b6c

Containers:

coredns:

Container ID:  containerd://194f8be3d70a7141148c63d2dd92c24e47e40af6c0fdb6d582885a60d38d8e62

Image:         coredns/coredns:1.8.0

Image ID:      docker.io/coredns/coredns@sha256:cc8fb77bc2a0541949d1d9320a641b82fd392b0d3d8145469ca4709ae769980e

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:       StartError

Message:      failed to create containerd task: failed to create shim: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: process_linux.go:508: setting cgroup config for procHooks process caused: openat2 /sys/fs/cgroup/kubepods/burstable/podfb1a1616-e10f-4916-9df8-160a92cf4340/194f8be3d70a7141148c63d2dd92c24e47e40af6c0fdb6d582885a60d38d8e62/memory.max: no such file or directory: unknown

Exit Code:    128

Started:      Thu, 01 Jan 1970 01:00:00 +0100

Finished:     Fri, 12 Aug 2022 18:32:26 +0200

Ready:          False

Restart Count:  6

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:  

Mounts:

/etc/coredns from config-volume (ro)

/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-hs9ph (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

kube-api-access-hs9ph:

Type:                    Projected (a volume that contains injected data from multiple sources)

TokenExpirationSeconds:  3607

ConfigMapName:           kube-root-ca.crt

ConfigMapOptional:       

DownwardAPI:             true

QoS Class:                   Burstable

Node-Selectors:              

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

Normal   Scheduled  4m42s                   default-scheduler  Successfully assigned kube-system/coredns-64c6478b6c-snkxx to raspberrypi4-docker3

Normal   Pulled     4m41s (x2 over 4m42s)   kubelet            Container image "coredns/coredns:1.8.0" already present on machine

Normal   Created    4m41s (x2 over 4m42s)   kubelet            Created container coredns

Warning  Failed     4m41s (x2 over 4m42s)   kubelet            Error: failed to create containerd task: failed to create shim: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: process_linux.go:508: setting cgroup config for procHooks process caused: openat2 /sys/fs/cgroup/kubepods/burstable/podfb1a1616-e10f-4916-9df8-160a92cf4340/coredns/memory.max: no such file or directory: unknown

Warning  BackOff    4m39s (x2 over 4m40s)   kubelet            Back-off restarting failed container

Normal   Pulled     2m32s (x4 over 3m51s)   kubelet            Container image "coredns/coredns:1.8.0" already present on machine

Normal   Created    2m32s (x4 over 3m51s)   kubelet            Created container coredns

Warning  Failed     2m32s (x4 over 3m51s)   kubelet            Error: failed to create containerd task: failed to create shim: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: process_linux.go:508: setting cgroup config for procHooks process caused: openat2 /sys/fs/cgroup/kubepods/burstable/podfb1a1616-e10f-4916-9df8-160a92cf4340/coredns/memory.max: no such file or directory: unknown

Warning  BackOff    2m30s (x13 over 3m51s)  kubelet            Back-off restarting failed container

How can I solve this CrashLoopBackOff problem?

[Amritpal]

I have solved the coredns problem by running

sudo sed -i '$ s/$/ cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1/' /boot/cmdline.txt

in my raspbian.