我有 2 个虚拟机，分别运行一个 kubernetes 主节点和一个在本地设置的从节点。到目前为止，一切都工作正常，但当我尝试使用 kubeadm init 命令启动 master 时，突然开始出现错误。我已 cpppied 下面的错误。
shayeeb@ubuntu:~$ sudo kubeadm init
[init] using Kubernetes version: v1.11.1
[preflight] running pre-flight checks
I0718 11:04:57.038464 20370 kernel_validator.go:81] Validating kernel version
I0718 11:04:57.038896 20370 kernel_validator.go:96] Validating kernel config
[preflight/images] Pulling images required for setting up a Kubernetes cluster
[preflight/images] This might take a minute or two, depending on the speed of your internet connection
[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'
[preflight] …