Hello Community,
We have a requirement of installing kubernetes 1.20.0 manually (private network without internet access) at customer environment.
We have downloaded the following executables for linux ubuntu distro:
https://storage.googleapis.com/kubernetes-release/release/v1.20.0/bin/linux/amd64/kubelet
https://storage.googleapis.com/kubernetes-release/release/v1.20.0/bin/linux/amd64/kubeadm
https://storage.googleapis.com/kubernetes-release/release/v1.20.0/bin/linux/amd64/kubectl
https://github.com/etcd-io/etcd/releases/download/v3.3.13/etcd-v3.3.13-linux-amd64.tar.gz
We unpacked and copied into /usr/local/bin directory. Also we verified the version by running the command:
kubeadm version
kubelet --version
kubectl version
and verified the executable is able to run and printout the version number.
We also added the the following to the directory kubelet.service.d:
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf
/etc/systemd/system/kubelet.service.d/10-kubeadm.conf contents:
[Unit]
Description=kubelet.service
[Service]
Type=simple
ExecStart=/usr/local/bin/kubelet
Restart=always
RestartSec=10
[Install]
WantedBy=multi-user.target
This is the error we are getting:
root@master:/etc/systemd/system/kubelet.service.d# sudo kubeadm init --pod-network-cidr=10.0.0.0/16
I0323 23:23:43.111842 234447 version.go:251] remote version is much newer: v1.23.5; falling back to: stable-1.20
[init] Using Kubernetes version: v1.20.15
[preflight] Running pre-flight checks
[WARNING FileExisting-socat]: socat not found in system path
[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.12. Latest validated version: 19.03
error execution phase preflight: [preflight] Some fatal errors occurred:
[ERROR FileExisting-conntrack]: conntrack not found in system path
[preflight] If you know what you are doing, you can make a check non-fatal with --ignore-preflight-errors=...
To see the stack trace of this error execute with --v=5 or higher
Could someone please help us for the fix of this issue.
Thanks
Cluster information:
Kubernetes version: 1.20.0
Installation method: Offline, manual
Host OS: Ubuntu 20.x