Redis Sentinel doesn't auto discover new slave instances - kubernetes

Question

I've deployed the redis helm chart on k8s with Sentinel enabled.
I've set up the Master-Replicas with Sentinel topology, it means one master and two slaves. Each pod is running both the redis and sentinel container successfully:
NAME READY STATUS RESTARTS AGE IP NODE
my-redis-pod-0 2/2 Running 0 5d22h 10.244.0.173 node-pool-u
my-redis-pod-1 2/2 Running 0 5d22h 10.244.1.96 node-pool-j
my-redis-pod-2 2/2 Running 0 3d23h 10.244.1.145 node-pool-e
Now, I've a python script that connects to redis and discovers the master by passing it the pod's ip.
sentinel = Sentinel([('10.244.0.173', 26379),
('10.244.1.96',26379),
('10.244.1.145',26379)],
sentinel_kwargs={'password': 'redispswd'})
host, port = sentinel.discover_master('mymaster')
redis_client = StrictRedis(
host=host,
port=port,
password='redispswd')
Let's suposse the master node is on my-redis-pod-0, when I do kubectl delete pod to simulate a problem that leads me to loss the pod, Sentinel will promote one of the others slaves to master and kubernetes will give me a new pod with redis and sentinel.
NAME READY STATUS RESTARTS AGE IP NODE
my-redis-pod-0 2/2 Running 0 3m 10.244.0.27 node-pool-u
my-redis-pod-1 2/2 Running 0 5d22h 10.244.1.96 node-pool-j
my-redis-pod-2 2/2 Running 0 3d23h 10.244.1.145 node-pool-e
The question is, how can I do to tell Sentinel to add this new ip to the list automatically (without code changes)?
Thanks!

Answer 1

Instead of using IPs, you may use the dns entries for a headless service.
A headless service is created by explicitly specifying
ClusterIP: None
Then you will be able to use the dns entries as under, where redis-0 will be the master
#syntax
pod_name.service_name.namespace.svc.cluster.local
#Example
redis-0.redis.redis.svc.cluster.local
redis-1.redis.redis.svc.cluster.local
redis-2.redis.redis.svc.cluster.local
References:
What is a headless service, what does it do/accomplish, and what are some legitimate use cases for it?
https://www.containiq.com/post/deploy-redis-cluster-on-kubernetes