Kubernetes 集群ca验证
创建集群时跳过ca验证
# vim /etc/kubernetes/apiserver 去除KUBE_ADMISSION_CONTROL中的 SecurityContextDeny,ServiceAccount #重启服务 systemctl restart kube-apiserver.service
创建集群时安装ca验证
在一个安全的内网环境中,kubernetes的各个组件需要与master之间可以通过apiserver的非安全端口进行连接,但如果对外,安全的做法需要启用https安全机制,这里采用CA签名的双向数字证书认证方式:
(1)为kube-apiserver生成一个数字证书,并用CA证书进行签名。 (2)为kube-apiserver进程配置证书相关的启动参数,包括CA证书(用于验证客户端证书的签名真伪、自己经过CA签名后的证书及私钥)。 (3)为每个访问Kubernetes API Server的客户端进程生成自己的数字证书,也都用CA证书进行签名,在相关程序的启动参数中增加CA证书、自己的证书等相关参数。
master端配置
使用OpenSSL工具在Master服务器上创建CA证书和私钥相关的文件
#openssl genrsa -out ca.key 2048 #openssl req -x509 -new -nodes -key ca.key -subj "/CN=192.168.132.148" -days 5000 -out ca.crt #masterip,这里/CN的值通常为域名 #openssl genrsa -out server.key 2048 #生成文件 ca.crt cat.key server.key
创建master_ssl.cnf文件,生成x509 v3版本证书
[req] req_extensions = v3_req distinguished_name = req_distinguished_name [req_distinguished_name] [ v3_req ] basicConstraints = CA:FALSE keyUsage = nonRepudiation, digitalSignature, keyEncipherment subjectAltName = @alt_names [alt_names] DNS.1 = kubernetes DNS.2 = kubernetes.default DNS.3 = kubernetes.default.svc DNS.4 = kubernetes.default.svc.cluster.local DNS.5 = k8s_master #master hostname IP.1 = 10.254.0.1 #master clusterip 可通过kubectl get service获取 IP.2 = 192.168.132.148 #master ip
基于Master_ssl.cnf生成server.csr和server.crt文件,生成时 -subj 参数中的“/CN”指定的名字应为master所在主机的主机名
openssl req -new -key server.key -subj "/CN=k8s_master" -config Master_ssl.cnf -out server.csr #/CN为master 主机名 openssl x509 -req -in server.csr -CA ca.crt -CAkey ca.key -CAcreateserial -days 5000 -extensions v3_req -extfile Master_ssl.cnf -out server.crt #目前文件有如下,将他们复制到 /etc/kubernetes/ssl/下ca.crt ca.key ca.srl server.crt server.csr server.key
配置kube-apiserver的启动参数
[root@k8s_master kubernetes]# cat apiserver |grep -v '^#\|^$' KUBE_API_ADDRESS="--advertise-address=192.168.132.148 --bind-address=192.168.132.148 --insecure-bind-address=192.168.132.148" KUBELET_PORT="--kubelet-port=10250" KUBE_ETCD_SERVERS="--etcd-servers=http://192.168.132.148:2379,http://192.168.132.136:2379,http://192.168.132.149:2379" KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16" KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota" KUBE_API_ARGS="--insecure-port=0 --secure-port=443 --client-ca-file=/etc/kubernetes/ssl/ca.crt --tls-private-key-file=/etc/kubernetes/ssl/server.key --tls-cert-file=/etc/kubernetes/ssl/server.crt" #解释说明kube_api_args中红色字体可不写(根据需求配置端口等,以及下面的配置),其作用为关闭非安全端口 8080,同时设置安全端口443,默认为6443 --client-ca-file #CA根证书文件 --tls-cert-file #服务端证书文件 --tls-private-key-file #服务端私钥文件 --secure-port=6443 #安全端口 --bind-address=192.168.1323.148 #HTTPS(安全)绑定的MasterIp地址 --advertise-address=192.168.132.148 #对外提供服务的IP --insecure-bind-address=192.168.132.148 #非安全IP
配置kube-controller-manager的启动参数
[root@k8s_master kubernetes]# cat controller-manager |grep -v '^#\|^$' KUBE_CONTROLLER_MANAGER_ARGS="--master=https://192.168.132.148:6443 --address=127.0.0.1 --service-account-private-key-file=/etc/kubernetes/ssl/server.key --root-ca-file=/etc/kubernetes/ssl/ca.crt --kubeconfig=/etc/kubernetes/kubeconfig" KUBELET_ADDRESSES="--machines= 192.168.132.136,192.168.132.149" #注:红色字体部分可不写
配置kube-scheduler的启动参数
[root@k8s_master kubernetes]# cat scheduler |grep -v '^#\|^$' KUBE_SCHEDULER_ARGS="--master=https://192.168.132.148:6443 --address=127.0.0.1 --kubeconfig=/etc/kubernetes/kubeconfig" #注:红色字体部分可不写
配置/etc/kubernetes/config
[root@k8s_master kubernetes]# cat config |grep -v '^#\|^$' KUBE_LOGTOSTDERR="--logtostderr=true" KUBE_LOG_LEVEL="--v=0" KUBE_ALLOW_PRIV="--allow-privileged=true" KUBE_MASTER="--master=https://192.168.132.148:6443"
生成集群管理员证书(kube-controller-manager的客户端证书、私钥和启动参数)
#cd /etc/kubernetes/ssl/ openssl genrsa -out cs_client.key 2048 openssl req -new -key cs_client.key -subj "/CN=k8s_master" -out cs_client.csr openssl x509 -req -in cs_client.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out cs_client.crt -days 5000
注:
在生成cs_client.crt时 -CA参数和-CAkey参数使用的是apiserver的ca.crt和ca.key文件 (然后将这些文件复制到一个目录中/etc/kubernetes/ssl/)
创建/etc/kubernetes/kubeconfig
apiVersion: v1
kind: Config
users:
- name: controllermanager
user:
client-certificate: /etc/kubernetes/ssl/cs_client.crt
client-key: /etc/kubernetes/ssl/cs_client.key
clusters:
- name: local
cluster:
certificate-authority: /etc/kubernetes/ssl/ca.crt
contexts:
- context:
cluster: local
user: controllermanager
name: my-context
current-context: my-context
重启kube-controller-manager、kube-scheduler、kube-apiserver服务
systemctl restart kube-scheduler kube-controller-manager
Node端配置
复制master主机下kube-apiserver的ca.crt和ca.key到各个Node 主机/etc/kubernetes/ssl下
生成kubelet_client.crt
在生成kubelet_client.crt时,-CA参数和-CAkey参数使用的是apiserver的ca.crt和ca.key文件。在生成kubelet_client.csr时,-subj参数中的“/CN”设置为本Node的IP地址。 openssl genrsa -out kubelet_client.key 2048 openssl req -new -key kubelet_client.key -subj "/CN=192.168.132.136" -out kubelet_client.csropenssl x509 -req -in kubelet_client.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out kubelet_client.crt -days 5000
创建/etc/kubernetes/kubeconfig
apiVersion: v1
kind: Config
users:
- name: kubelet
user:
client-certificate: /etc/kubernetes/ssl/kubelet_client.crt
client-key: /etc/kubernetes/ssl/kubelet_client.key
clusters:
- name: local
cluster:
certificate-authority: /etc/kubernetes/ssl/ca.crt
contexts:
- context:
cluster: local
user: kubelet
name: my-context
current-context: my-context
修改kubernetes的配置文件/etc/kubernetes/config
[root@k8s_node1 kubernetes]# cat /etc/kubernetes/config|grep -v '^#\|^$' KUBE_LOGTOSTDERR="--logtostderr=true" KUBE_LOG_LEVEL="--v=0" KUBE_ALLOW_PRIV="--allow-privileged=false" KUBE_MASTER="--master=https://192.168.132.148:6443"
修改/etc/kubernetes/kubelet
[root@k8s_node1 kubernetes]# cat /etc/kubernetes/kubelet|grep -v '^#\|^$' KUBELET_ADDRESS="--address=192.168.132.136" KUBELET_HOSTNAME="--hostname-override=192.168.132.136" KUBELET_API_SERVER="--api-servers=https://192.168.132.148:6443" KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest" KUBELET_ARGS="--api-servers=https://192.168.132.148:6443 --cluster_dns=10.254.10.2 --cluster_domain=cluster.local --kubeconfig=/etc/kubernetes/kubeconfig" 注:红色字体部分可不写,根据实际情况配置
设置kube-proxy服务的启动参数
[root@k8s_node1 kubernetes]# cat /etc/kubernetes/proxy|grep -v '^#\|^$' KUBE_PROXY_ARGS="--master=https://192.168.132.148:6443 --kubeconfig=/etc/kubernetes/kubeconfig"
重启kube-proxy、kubelet服务
systemctl restart kubelet systemctl restart kube-proxy
验证
删除master下etcd中的旧数据
#master执行 etcdctl rm --recursive registry
重启master上的服务
#systemctl daemon-reload #systemctl restart etcd kube-apiserver kube-scheduler kube-controller-manager
重启node上的服务
systemctl daemon-reload systemctl restart docker kubelet kube-proxy
验证
[root@k8s_master kubernetes]# curl https://192.168.132.148:6443/api/v1/nodes --cert /etc/kubernetes/ssl/cs_client.crt --key /etc/kubernetes/ssl/cs_client.key --cacert /etc/kubernetes/ssl/ca.crt
{
"kind": "NodeList",
"apiVersion": "v1",
"metadata": {
"selfLink": "/api/v1/nodes",
"
},
"items": [
{
"metadata": {
"name": "192.168.132.136",
"selfLink": "/api/v1/nodes/192.168.132.136",
"uid": "f740f219-2b4a-11e8-bc10-000c29c38a0c",
",
"creationTimestamp": "2018-03-19T07:56:01Z",
"labels": {
"beta.kubernetes.io/arch": "amd64",
"beta.kubernetes.io/os": "linux",
"kubernetes.io/hostname": "192.168.132.136"
},
"annotations": {
"volumes.kubernetes.io/controller-managed-attach-detach": "true"
}
},
"spec": {
"externalID": "192.168.132.136"
},
"status": {
"capacity": {
",
",
"memory": "999920Ki",
"
},
"allocatable": {
",
",
"memory": "999920Ki",
"
},
"conditions": [
{
"type": "OutOfDisk",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:42Z",
"lastTransitionTime": "2018-03-19T07:56:01Z",
"reason": "KubeletHasSufficientDisk",
"message": "kubelet has sufficient disk space available"
},
{
"type": "MemoryPressure",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:42Z",
"lastTransitionTime": "2018-03-19T07:56:01Z",
"reason": "KubeletHasSufficientMemory",
"message": "kubelet has sufficient memory available"
},
{
"type": "DiskPressure",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:42Z",
"lastTransitionTime": "2018-03-19T07:56:01Z",
"reason": "KubeletHasNoDiskPressure",
"message": "kubelet has no disk pressure"
},
{
"type": "Ready",
"status": "True",
"lastHeartbeatTime": "2018-03-19T09:10:42Z",
"lastTransitionTime": "2018-03-19T07:56:01Z",
"reason": "KubeletReady",
"message": "kubelet is posting ready status"
}
],
"addresses": [
{
"type": "LegacyHostIP",
"address": "192.168.132.136"
},
{
"type": "InternalIP",
"address": "192.168.132.136"
},
{
"type": "Hostname",
"address": "192.168.132.136"
}
],
"daemonEndpoints": {
"kubeletEndpoint": {
"Port": 10250
}
},
"nodeInfo": {
"machineID": "b3c5e7f95f9b4da99bcf0744f38f5eee",
"systemUUID": "87164D56-73D6-32A7-28F1-66EE23C27F10",
"bootID": "29849630-efce-4aa4-b690-ff45726b17a2",
"kernelVersion": "3.10.0-514.26.2.el7.x86_64",
"osImage": "CentOS Linux 7 (Core)",
"containerRuntimeVersion": "docker://1.12.6",
"kubeletVersion": "v1.5.2",
"kubeProxyVersion": "v1.5.2",
"operatingSystem": "linux",
"architecture": "amd64"
},
"images": [
{
"names": [
"index.tenxcloud.com/yexianwolail/gb-frontend@sha256:0be2894d43915ba057e5f892d7e0dac75dfa3765874dbc99ccd78ad26e6213de",
"index.tenxcloud.com/yexianwolail/gb-frontend:v4"
],
"sizeBytes": 512107183
},
{
"names": [
"index.tenxcloud.com/google_containers/redis@sha256:f066bcf26497fbc55b9bf0769cb13a35c0afa2aa42e737cc46b7fb04b23a2f25",
"index.tenxcloud.com/google_containers/redis:e2e"
],
"sizeBytes": 418929769
},
{
"names": [
"finance/centos6.8-base@sha256:1cb78ded75775ad289cf43c67141b39676bf3571cb20cd6a80e105c6497ae0e4",
"finance/centos6.8-base:latest"
],
"sizeBytes": 332467242
},
{
"names": [
"registry.access.redhat.com/rhel7/pod-infrastructure@sha256:01f829e96ba98a7ef5481359de7ea684c2fe41f2d28963e6c87370334a5256c4",
"registry.access.redhat.com/rhel7/pod-infrastructure:latest"
],
"sizeBytes": 208587465
},
{
"names": [
"docker.io/bestwu/kubernetes-dashboard-amd64@sha256:d820c9a0a0a7cd7d0c9d3630a2db0fc33d190db31f3e0797d4df9dc4a6a41c6b",
"docker.io/bestwu/kubernetes-dashboard-amd64:v1.6.3"
],
"sizeBytes": 138972432
},
{
"names": [
"ubuntu@sha256:84c334414e2bfdcae99509a6add166bbb4fa4041dc3fa6af08046a66fed3005f",
"ubuntu:latest"
],
"sizeBytes": 119509665
},
{
"names": [
"daocloud.io/megvii/kubernetes-dashboard-amd64@sha256:6e0218eeb940f0fc9ca68972bda2b9569921fed1ef793ba78e30900cc7ab9396",
"daocloud.io/megvii/kubernetes-dashboard-amd64:v1.8.0"
],
"sizeBytes": 119155776
},
{
"names": [
"index.tenxcloud.com/yexianwolail/gb-redisslave@sha256:9f13d46b2e4cac290aa9757f83dff26e0fa06802f898abec43ca22076966440a",
"index.tenxcloud.com/yexianwolail/gb-redisslave:v1"
],
"sizeBytes": 109462535
},
{
"names": [
"docker.io/nginx@sha256:004ac1d5e791e705f12a17c80d7bb1e8f7f01aa7dca7deee6e65a03465392072",
"docker.io/nginx:latest"
],
"sizeBytes": 108275923
},
{
"names": [
"swarm@sha256:1a05498cfafa8ec767b0d87d11d3b4aeab54e9c99449fead2b3df82d2744d345",
"swarm:latest"
],
"sizeBytes": 15771951
},
{
"names": [
"index.tenxcloud.com/google_containers/busybox@sha256:4bdd623e848417d96127e16037743f0cd8b528c026e9175e22a84f639eca58ff",
"index.tenxcloud.com/google_containers/busybox:1.24"
],
"sizeBytes": 1113554
}
]
}
},
{
"metadata": {
"name": "192.168.132.149",
"selfLink": "/api/v1/nodes/192.168.132.149",
"uid": "7321176a-2b49-11e8-bc10-000c29c38a0c",
",
"creationTimestamp": "2018-03-19T07:45:09Z",
"labels": {
"beta.kubernetes.io/arch": "amd64",
"beta.kubernetes.io/os": "linux",
"kubernetes.io/hostname": "192.168.132.149"
},
"annotations": {
"volumes.kubernetes.io/controller-managed-attach-detach": "true"
}
},
"spec": {
"externalID": "192.168.132.149"
},
"status": {
"capacity": {
",
",
"memory": "999920Ki",
"
},
"allocatable": {
",
",
"memory": "999920Ki",
"
},
"conditions": [
{
"type": "OutOfDisk",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:44Z",
"lastTransitionTime": "2018-03-19T07:45:09Z",
"reason": "KubeletHasSufficientDisk",
"message": "kubelet has sufficient disk space available"
},
{
"type": "MemoryPressure",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:44Z",
"lastTransitionTime": "2018-03-19T07:45:09Z",
"reason": "KubeletHasSufficientMemory",
"message": "kubelet has sufficient memory available"
},
{
"type": "DiskPressure",
"status": "False",
"lastHeartbeatTime": "2018-03-19T09:10:44Z",
"lastTransitionTime": "2018-03-19T07:45:09Z",
"reason": "KubeletHasNoDiskPressure",
"message": "kubelet has no disk pressure"
},
{
"type": "Ready",
"status": "True",
"lastHeartbeatTime": "2018-03-19T09:10:44Z",
"lastTransitionTime": "2018-03-19T07:45:19Z",
"reason": "KubeletReady",
"message": "kubelet is posting ready status"
}
],
"addresses": [
{
"type": "LegacyHostIP",
"address": "192.168.132.149"
},
{
"type": "InternalIP",
"address": "192.168.132.149"
},
{
"type": "Hostname",
"address": "192.168.132.149"
}
],
"daemonEndpoints": {
"kubeletEndpoint": {
"Port": 10250
}
},
"nodeInfo": {
"machineID": "0e3f05a02b4046c2a29f626cd4af4e5f",
"systemUUID": "0B514D56-1364-0109-7339-5D0772899205",
"bootID": "320c4977-903b-4b46-a295-9cb601ae9e44",
"kernelVersion": "3.10.0-514.26.2.el7.x86_64",
"osImage": "CentOS Linux 7 (Core)",
"containerRuntimeVersion": "docker://1.12.6",
"kubeletVersion": "v1.5.2",
"kubeProxyVersion": "v1.5.2",
"operatingSystem": "linux",
"architecture": "amd64"
},
"images": [
{
"names": [
"index.tenxcloud.com/yexianwolail/gb-frontend@sha256:0be2894d43915ba057e5f892d7e0dac75dfa3765874dbc99ccd78ad26e6213de",
"index.tenxcloud.com/yexianwolail/gb-frontend:v4"
],
"sizeBytes": 512107183
},
{
"names": [
"finance/centos6.8-base@sha256:1cb78ded75775ad289cf43c67141b39676bf3571cb20cd6a80e105c6497ae0e4",
"finance/centos6.8-base:latest"
],
"sizeBytes": 332467242
},
{
"names": [
"registry.access.redhat.com/rhel7/pod-infrastructure@sha256:01f829e96ba98a7ef5481359de7ea684c2fe41f2d28963e6c87370334a5256c4",
"registry.access.redhat.com/rhel7/pod-infrastructure:latest"
],
"sizeBytes": 208587465
},
{
"names": [
"docker.io/bestwu/kubernetes-dashboard-amd64@sha256:d820c9a0a0a7cd7d0c9d3630a2db0fc33d190db31f3e0797d4df9dc4a6a41c6b",
"docker.io/bestwu/kubernetes-dashboard-amd64:v1.6.3"
],
"sizeBytes": 138972432
},
{
"names": [
"ubuntu@sha256:84c334414e2bfdcae99509a6add166bbb4fa4041dc3fa6af08046a66fed3005f",
"ubuntu:latest"
],
"sizeBytes": 119509665
},
{
"names": [
"index.tenxcloud.com/yexianwolail/gb-redisslave@sha256:9f13d46b2e4cac290aa9757f83dff26e0fa06802f898abec43ca22076966440a",
"index.tenxcloud.com/yexianwolail/gb-redisslave:v1"
],
"sizeBytes": 109462535
},
{
"names": [
"docker.io/nginx@sha256:004ac1d5e791e705f12a17c80d7bb1e8f7f01aa7dca7deee6e65a03465392072",
"docker.io/nginx:latest"
],
"sizeBytes": 108275923
},
{
"names": [
"index.tenxcloud.com/google_containers/skydns@sha256:a317df077c678e684790c22902ff4040393cc172abe245d4b478bac6dbdd8052",
"index.tenxcloud.com/google_containers/skydns:2015-10-13-8c72f8c"
],
"sizeBytes": 40547562
},
{
"names": [
"index.tenxcloud.com/google_containers/etcd-amd64@sha256:94573e18def7a39c277a3b088b4d5332c3f68492bb73ac66f7f93c12cdd1356c",
"index.tenxcloud.com/google_containers/etcd-amd64:2.2.1"
],
"sizeBytes": 28192476
},
{
"names": [
"index.tenxcloud.com/google_containers/kube2sky@sha256:edafbc690dd3c95ea321a83ace5dac4750095920f8a565cef37dd8438ee509c4",
"index.tenxcloud.com/google_containers/kube2sky:1.14"
],
"sizeBytes": 27804037
},
{
"names": [
"swarm@sha256:1a05498cfafa8ec767b0d87d11d3b4aeab54e9c99449fead2b3df82d2744d345",
"swarm:latest"
],
"sizeBytes": 15771951
},
{
"names": [
"index.tenxcloud.com/google_containers/exechealthz@sha256:512fad89cb2e76b24f12884bab4117a85733ebe033f18f8da34b617fbfa03708",
"index.tenxcloud.com/google_containers/exechealthz:1.0"
],
"sizeBytes": 7095869
},
{
"names": [
"index.tenxcloud.com/google_containers/busybox@sha256:4bdd623e848417d96127e16037743f0cd8b528c026e9175e22a84f639eca58ff",
"index.tenxcloud.com/google_containers/busybox:1.24"
],
"sizeBytes": 1113554
}
]
}
}
]
}
执行kubectl get nodes 报错:
报错信息如下: The connection to the server localhost:8080 was refused - did you specify the right host or port?
用如下命令代替
kubectl -s 192.168.132.148:8080 get nodes
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