Kubernetes 修改kubelet启动参数

背景

最近，我在虚拟机上通过rpm包安装了k8s集群。我想创建静态Pod，那么就需要更改kubelet的启动参数。相关环境信息如下：

role	OS	IP	module
Master	Centos7.2	10.1.2.182	kube-apiserver kube-controller-manager kube-scheduler
Node1	Centos7.2	10.1.2.183	kubelet kube-proxy
Node2	Centos7.2	10.1.2.184	kubelet kube-proxy

一、查看kubelet启动参数

k8s组件是通过systemctl来管理的，因此可以在 /etc/systemd/system 或 /usr/lib/systemd/system下查找相关配置文件

找到kubelet对应服务的配置文件目录
# cd /etc/systemd/system/kubelet.service.d/   

查看原文件内容
# cat 10-kubeadm.conf
[Service]
Environment="KUBELET_KUBECONFIG_ARGS=--kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"
Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
Environment="KUBELET_DNS_ARGS=--cluster-dns=10.12.0.10 --cluster-domain=cluster.local"
Environment="KUBELET_EXTRA_ARGS=--v=4"
ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_EXTR
A_ARGS

查看kubelet的相关启动参数
# ps -ef | grep kubelet
/usr/bin/kubelet --require-kubeconfig=true --pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true --network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin --cluster-dns=10.12.0.10 --cluster-domain=cluster.local --v=4

二、修改kubelet启动参数

添加一个新的参数 –config

# vim 10-kubeadm.conf
[Service]
Environment="KUBELET_KUBECONFIG_ARGS=--config=/etc/kubelet.d/ --kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"
Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
Environment="KUBELET_DNS_ARGS=--cluster-dns=10.12.0.10 --cluster-domain=cluster.local"
Environment="KUBELET_EXTRA_ARGS=--v=4"
ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_EXTR
A_ARGS

执行如下命令使新增参数生效
# systemctl stop kubelet
# systemctl daemon-reload
# systemctl start kubelet

检查新增参数是否已经生效
# ps -ef | grep kubelet
/usr/bin/kubelet --config=/etc/kubelet.d/ --kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true --pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true --network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin --cluster-dns=10.12.0.10 --cluster-domain=cluster.local --v=4

同理，此方法也可添加kubelet其他启动参数。