redis-cli -h redis-redis-ha -p 26479

$ kubectl get po | grep redis

NAME                                                     READY   STATUS      RESTARTS   AGE
redis-1-redis-ha-server-0                                3/3     Running     0          3d4h
redis-1-redis-ha-server-1                                3/3     Running     0          3d5h
redis-1-redis-ha-server-2                                3/3     Running     0          3d4h

sentinel:
  port: 26379
  quorum: 2
  config:
    ## Additional sentinel conf options can be added below. Only options that
    ## are expressed in the format simialar to 'sentinel xxx mymaster xxx' will
    ## be properly templated.
    ## For available options see http://download.redis.io/redis-stable/sentinel.conf
    down-after-milliseconds: 10000
    ## Failover timeout value in milliseconds
    failover-timeout: 180000
    parallel-syncs: 5

  ## Custom sentinel.conf files used to override default settings. If this file is
  ## specified then the sentinel.config above will be ignored.
  # customConfig: |-
      # Define configuration here

  resources: {}
  #  requests:
  #    memory: 200Mi
  #    cpu: 100m
  #  limits:
  #    memory: 200Mi

kubectl logs -f redis-1-redis-ha-server-0

kubectl delete po redis-1-redis-ha-server-1

# 使用 kubectl 連入，多個 container 要明確指出連入的 container
kubectl exec -it redis-1-redis-ha-server-0 --container redis sh

redis-cli -h redis-redis-ha -p 26479

# 近來先 ping 一下
$ ping
PONG

# 列出所有 master 的資訊，以及設定資訊
sentinel master
redis-2-redis-ha:26379> sentinel masters
1)  1) "name"
    2) "mymaster"
    3) "ip"
    4) "10.15.242.245"
    5) "port"
    6) "6379"
    7) "runid"
    8) "63a97460b7c3745577931dad406df9609c4e2464"
    9) "flags"
   10) "master"
   11) "link-pending-commands"
   12) "0"
   13) "link-refcount"
   14) "1"
   15) "last-ping-sent"
   16) "0"
   17) "last-ok-ping-reply"
   18) "479"
   19) "last-ping-reply"
   20) "479"
   21) "down-after-milliseconds"
   22) "5000"
   23) "info-refresh"
   24) "5756"
   25) "role-reported"
   26) "master"
   27) "role-reported-time"
   28) "348144787"
   29) "config-epoch"
   30) "13"
   31) "num-slaves"
   32) "2"
   33) "num-other-sentinels"
   34) "2"
   35) "quorum"
   36) "2"
   37) "failover-timeout"
   38) "180000"
   39) "parallel-syncs"
   40) "5"

# 取得集群中的 master 訊息，目前有一個 master
$ sentinel master mymaster

# 取得集群中的 slaves 訊息，目前有兩個 slave
$ sentinel slaves mymaster

# 取得集群中的 master 訊息
$ sentinel sentinels mymaster

# 檢查 sentinel 的 quorum
$ sentinel ckquorum mymaster

OK 3 usable Sentinels. Quorum and failover authorization can be reached

# 強迫觸發一次 failover
sentinel failover mymaster

# 使用獨立的 pod service 連入 sentinel，協助彼此識別
sntnl := &sentinel.Sentinel{
	Addrs:      []string{"redis-2-redis-ha-announce-0:26379", "redis-2-redis-ha-announce-0:26379", "redis-2-redis-ha-announce-0:26379"},
	MasterName: "mymaster",
	Dial: func(addr string) (redis.Conn, error) {
		timeout := 500 * time.Millisecond
		c, err := redis.DialTimeout("tcp", addr, timeout, timeout, timeout)
		if err != nil {
			return nil, err
		}
		return c, nil
	},
}

# 產生 connection pool
return &redis.Pool{
	MaxIdle:     3,
	MaxActive:   64,
	Wait:        true,
	IdleTimeout: 240 * time.Second,
	Dial: func() (redis.Conn, error) {

    # 透過 sentinel 取得 master address，如果 master 死了，再執行可以拿到新的 master
		masterAddr, err := sntnl.MasterAddr()
		if err != nil {
			return nil, err
		}
		c, err := redis.Dial("tcp", masterAddr)
		if err != nil {
			return nil, err
		}
		return c, nil
	},
	TestOnBorrow: func(c redis.Conn, t time.Time) error {
		if !sentinel.TestRole(c, "master") {
			return errors.New("Role check failed")
		} else {
			return nil
		}
	},
}