6个节点是不是应该配置成3组主从模式？

是的，您说得对。Redis Cluster 的节点应该配置成 3 组主从模式，每一组有 1 个主节点和 1 个或多个从节点。这样可以保证 Redis Cluster 的高可用性和数据冗余。在 YAML 文件中，您需要按照主从模式的方式配置 `StatefulSet` 和 `redis.conf` 文件。

下面是一个配置 6 个节点、3 组主从模式的 Redis Cluster 的 YAML 配置文件示例（假设每组主从节点分别为 `redis-0`、`redis-1`、`redis-2`）：

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: redis-cluster
  namespace: default
spec:
  serviceName: redis-cluster
  replicas: 6
  selector:
    matchLabels:
      app: redis-cluster
  template:
    metadata:
      labels:
        app: redis-cluster
    spec:
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
                - key: app
                  operator: In
                  values:
                  - redis-cluster
            topologyKey: "kubernetes.io/hostname"
      containers:
      - name: redis
        image: redis:6.2.5-alpine
        command:
        - sh
        - -c
        - "redis-server /redis/redis.conf"
        ports:
        - containerPort: 6379
          name: client
        - containerPort: 16379
          name: gossip
        volumeMounts:
        - name: redis-conf
          mountPath: /redis
        resources:
          limits:
            cpu: 100m
            memory: 128Mi
          requests:
            cpu: 100m
            memory: 128Mi
      volumes:
      - name: redis-conf
        configMap:
          name: redis-cluster-config
          items:
          - key: redis.conf
            path: redis.conf
---
apiVersion: v1
kind: Service
metadata:
  name: redis-cluster
  namespace: default
spec:
  type: ClusterIP
  selector:
    app: redis-cluster
  ports:
  - name: client
    port: 6379
    targetPort: 6379
  - name: gossip
    port: 16379
    targetPort: 16379
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: redis-cluster-config
  namespace: default
data:
  redis.conf: |
    cluster-enabled yes
    cluster-config-file nodes.conf
    cluster-node-timeout 5000
    appendonly yes
    protected-mode no
    cluster-announce-ip {{POD_IP}}
    cluster-announce-port 6379
    cluster-announce-bus-port 16379
    cluster-announce-node-type {{NODE_TYPE}}
    cluster-announce-require-auth {{AUTH_PASS}}
    requirepass {{AUTH_PASS}}
    masterauth {{AUTH_PASS}}

其中，`{{POD_IP}}` 为 Kubernetes 中的 Pod IP 地址，`{{NODE_TYPE}}` 为节点类型（`master` 或 `slave`），`{{AUTH_PASS}}` 为 Redis 访问的密码。您需要根据实际情况替换这些变量的值。