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

最新文章

  1. 【译】RabbitMQ：Topics
  2. [异常解决] MPU6050启动异常读出陀螺仪和加速度计的值全为0的解决办法
  3. mysql-mysql悲观锁和乐观锁
  4. 【leetcode】Unique Binary Search Trees
  5. json数据类型
  6. H2嵌入式数据库
  7. python函数应用
  8. Setup Entity Framework Environment
  9. searchDisplayController 时引起的数组越界
  10. jquery中获取当前点击对象
  11. 写一个兼容性比较好的拖拽DEMO
  12. 完美世界3D格斗手游[格斗宝贝]今日公測
  13. Javascript写的一个可拖拽排序的列表
  14. Leetcode：Two Sum
  15. FFMPEG类库打开流媒体的方法（需要传参数的时候）
  16. 基于jQuery的控件：弹框
  17. Web App架构
  18. 第二个项目：WC
  19. context日志
  20. Windows下memcache的配置和使用(python)

热门文章

  1. Cent OS安装使用ffmpeg（完整版）
  2. Android 根据版本号更新
  3. 二分图最小点覆盖König定理的简单证明 （加入自己理解）
  4. codechef EBAIT Election Bait【欧几里得算法】
  5. bzoj 2054: 疯狂的馒头(线段树||并查集）
  6. Android性能优化案例研究
  7. THUSC2017题解
  8. This license xxx has been cancelled 解决
  9. InnoDB，5项最佳实践，知其所以然？
  10. 10元买啤酒问题Java解法