Quick and dirty Redis cluster taking advantage of Redis Sentinel for automatic failover. Persistence is turned off by default.
- Setup docker swarm
- Create a overlay network:
docker network create --attachable --driver overlay redis- Modify scripts/docker-compose.yml to how you want to deploy the stack.
- Run
scripts/bootstrap.sh.
bash scripts/bootstrap.sh latest- Connect to with redis-cli
docker run --rm --network redis -ti redis:4.0.11-alpine redis-cli -h redisTo access the redis cluster outside of docker, port 6379 needs to be expose. This can be done by adding ports to the docker-compose file:
...
redis:
image: thomasjpfan/redis-look
ports:
- "6379:6379"
...A docker service called redis-zero is created to serve as the initial master for the redis sentinels to setup. The redis-look instances watches the redis sentinels for a master, and connects to redis-zero once a master has been decided. Once the dust has settled, remove the redis-zero instance and wait for failover to take over so a new redis-master will take over. Use redis-utils to reset sentinels so that its metadata is accurate with the correct state.
The use of redis-zero as a bootstrapping step allows for the docker-compose.yml to provide only the long running services:
version: '3.1'
services:
redis-sentinel:
image: thomasjpfan/redis-sentinel
environment:
- REDIS_IP=redis-zero
- REDIS_MASTER_NAME=redismaster
deploy:
replicas: 3
networks:
- redis
redis:
image: thomasjpfan/redis-look
environment:
- REDIS_SENTINEL_IP=redis-sentinel
- REDIS_MASTER_NAME=redismaster
- REDIS_SENTINEL_PORT=26379
deploy:
replicas: 3
networks:
- redis
networks:
redis:
external: true
From now on just scale redis to expand the number of slaves or scale redis-sentinel to increase the number of sentinels.