部署dhcpd服务器

Question

我正在尝试在我的Kubernetes集群上的pod中部署DHCP服务器。我创建了以下资源：

$ cat dhcpd-deployment.yaml

kind: Deployment
metadata:
  name: dhcpd
  namespace: kube-mngt
spec:
  selector:
    matchLabels:
      app: dhcpd
  replicas: 1
  template:
    metadata:
      labels:
        app: dhcpd
    spec:
      nodeSelector:
        kubernetes.io/hostname: neo1
      containers:
      - name: dhcpd
        image: 10.0.100.1:5000/dhcpd:latest
        volumeMounts:
        - name: dhcpd-config
          mountPath: /etc/dhcp
      volumes:
        - name: dhcpd-config
          persistentVolumeClaim:
            claimName: dhcpd-config-volume-claim

$ kubectl create -f dhcpd-deployment.yaml

$ cat dhcpd-service.yaml

apiVersion: v1

kind: Service
metadata:
  name: dhcpd
  namespace: kube-mngt
spec:
  selector:
    app: dhcpd
  ports:
  - name: dhcp
    protocol: UDP
    port: 67
    targetPort: 67

$ kubectl create -f dhcpd-service.yaml

一切都是成功创建，pod和服务但不幸的是，DHCPD pod在UDP端口67上没有收到任何数据包。

我错过了什么？

Answer 1

我找到了使dhcpd pod运行良好的解决方案。以下示例是服务于k8s服务网络（clusterIPs）之外的外部网络。 dhcp配置如下：

include "/etc/dhcp/dhcpd-options.conf";

subnet 192.168.0.0 netmask 255.255.0.0 {}

# management network
subnet 10.0.0.0 netmask 255.255.0.0 {
  option routers 10.0.255.254;
  option broadcast-address 10.0.255.255;
  next-server 10.0.100.6;
  include "/etc/dhcp/lease-bmc.conf";
  include "/etc/dhcp/lease-node.conf";
}

k8s服务如下：

$ cat dhcpd-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: dhcpd
  namespace: kube-mngt
spec:
  selector:
    app: dhcpd
  ports:
  - protocol: UDP
    port: 67
    targetPort: 67
  externalIPs:
  - 10.0.100.5

然后，配置交换机（接口vlan X）以指定指向dhcp服务器的帮助程序地址（在我们的示例中为10.0.100.5）

interface Vlan1
 ip address 10.0.255.254 255.255.0.0 secondary
 ip address 10.0.0.1 255.255.0.0
 ip helper-address 10.0.100.5
!