Error: redis cluster failed to refresh slots cache
What's Causing This Error
The error 'redis cluster failed to refresh slots cache' typically occurs when the Redis client is unable to map keys to appropriate nodes in your Redis cluster. This can happen due to several reasons:
- Network issues: If the network connection between your application and your Redis server is unreliable, causing intermittent connectivity issues.
- Misconfiguration: The client's configuration for its connection to the Redis cluster might be incorrect.
- Cluster changes: Slots mapping may fail if there has been a change in the cluster configuration (like adding or removing nodes) and the client wasn't able to update its slots cache accurately.
Solution - Here's How To Resolve It
Here are some steps you can take to resolve the error:
- Check Network Connectivity: Ensure stable and reliable network connection between your application and the Redis instances.
- Review Configuration: Review your Redis cluster's configuration to ensure that it's correct. Make sure the client's configuration matches with the actual state of the cluster.
- Update Client Library: If you're using an older client library, consider updating it. Newer versions often come with fixes and improved error handling, which could solve this issue.
- Manual Refresh: Try to manually refresh the slots cache. To do this, restart the client connection to force a fresh retrieval of cluster information:
from rediscluster import RedisCluster startup_nodes = [{"host": "127.0.0.1", "port": "7000"}] rc = RedisCluster(startup_nodes=startup_nodes, decode_responses=True) # Close existing connections to refresh slots rc.connection_pool.disconnect()
- Cluster Health Check: Verify the health of your Redis cluster. You can use the
redis-cli
tool to check the status of each node:
Look for fields likeredis-cli -c -h <node-ip> -p <node-port> cluster info
cluster_state:ok
and verify that all nodes are up and running without errors. - Redis Cluster Restart: As a last resort, consider restarting your Redis cluster, but keep in mind that this should only be done during a maintenance window or when the impact to your applications can be minimized. Use the following steps to restart:
sudo systemctl restart redis # or for Docker users docker restart <container_id>
Was this content helpful?
Other Common Redis Errors (with Solutions)
- could not connect to redis at 127.0.0.1:6379: connection refused
- redis error server closed the connection
- redis.exceptions.responseerror: value is not an integer or out of range
- redis.exceptions.responseerror moved
- redis.exceptions.responseerror noauth authentication required
- redis-server failed to start advanced key-value store
- spring boot redis unable to connect to localhost 6379
- unable to configure redis to keyspace notifications
- redis.clients.jedis.exceptions.jedismoveddataexception
- could not get resource from pool redis
- failed to restart redis service unit redis service not found
- job for redis-server.service failed because a timeout was exceeded
Switch & save up to 80%
Dragonfly is fully compatible with the Redis ecosystem and requires no code changes to implement. Instantly experience up to a 25X boost in performance and 80% reduction in cost