Does Redis provide a high level of fault tolerance?

Redis itself does not provide a high level of fault tolerance out of the box, as it is an in-memory storage, and data can be lost in case of server failure if disk persistence is not configured.

However, Redis supports mechanisms to improve fault tolerance:

• Replication: you can set up master-slave replication, where slaves can automatically switch to master in case of failure.
• Sentinel: a monitoring system with automatic failover between master and replicas.
• Redis Cluster: a distributed cluster with sharding and automatic failover.

To ensure high fault tolerance, Redis is usually deployed in a cluster with Sentinel or Redis Cluster, and regular data saving to disk (RDB or AOF) is also used.