[BUG] pcn-k8s doesn't start polycube pods, pointing kernel headers problem

[camilla-m]

Describe the bug

I'm trying to initialize pcn-k8s according to this tutorial in Vagrant, tried also Minikube and an EKS cluster. All of them returned to me similar errors like that:

Inside the polycube pods there's a CrashLoopBack error because one of the pods is not working due kernel issues.

To Reproduce

1. Up a Kubernetes cluster.
2. kubectl apply -f https://raw.githubusercontent.com/polycube-network/polycube/master/src/components/k8s/pcn-k8s.yaml inside cluster.
3. kubectl get pods -n kube-system -o wide | grep polycube to check polycube pods.

Expected behavior

Wanted to follow this tutorial and keep doing commands like kubectl exec -it polycube-xxxxx -n kube-system -c polycube-k8s polycubectl show cubesv

Please tell us about your environment:

1. OS details: cat /etc/*-release

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.2 LTS"
NAME="Ubuntu"
VERSION="20.04.2 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.2 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal

2. Kernel details: uname -a
Linux camipunk 5.11.0-44-generic #48~20.04.2-Ubuntu SMP Tue Dec 14 15:36:44 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
3. Polycube Version: polycubectl version
polycubenets/polycube-k8s:latest image from Docker Hub

[ekoops]

Hi @camilla-m. I think the problem is due to the kernel version used by your nodes. You could try to downgrade to a lower kernel version: 5.4.0-91-generic should work.