unable to join worker node to master node in k8 - kubernetes

Question

when using kubeadm join token to join worker node to a k8 master. Iam receiving following errors.
[preflight] running pre-flight checks
[preflight] WARNING: Couldn't create the interface used for talking to the container runtime: docker is required for container runtime: exec: "docker": executable file not found in $PATH
[WARNING RequiredIPVSKernelModulesAvailable]: the IPVS proxier will not be used, because the following required kernel modules are not loaded: [ip_vs_sh nf_conntrack_ipv4 ip_vs ip_vs_rr ip_vs_wrr] or no builtin kernel ipvs support: map[ip_vs:{} ip_vs_rr:{} ip_vs_wrr:{} ip_vs_sh:{} nf_conntrack_ipv4:{}]
you can solve this problem with following methods:
1. Run 'modprobe -- ' to load missing kernel modules;
2. Provide the missing builtin kernel ipvs support
[preflight] Some fatal errors occurred:
[ERROR FileContent--proc-sys-net-bridge-bridge-nf-call-iptables]: /proc/sys/net/bridge/bridge-nf-call-iptables does not exist
[ERROR FileContent--proc-sys-net-ipv4-ip_forward]: /proc/sys/net/ipv4/ip_forward contents are not set to 1
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`
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error 2 : when run modprobe_nrfilter
modprobe: FATAL: Module br_netfilter not found.

Answer 1

It seems like docker is not installed or not in your PATH:
Couldn't create the interface used for talking to the container runtime: docker is required for container runtime: exec: "docker": executable file not found in $PATH
This can be fixed by installing docker and ensuring the docker executable is in your PATH.