How does Redis address the issue of data loss?

There are several ways in which Redis can address issues with data loss.

1. Persistence Mechanism: Redis supports two types of persistence mechanisms, namely RDB (Redis Database) and AOF (Append Only File).
2. RDB: Saving a snapshot of Redis data at a certain point in time onto the disk can be done automatically by configuring periodic snapshot saving, or manually by executing the SAVE or BGSAVE command. When Redis is restarted, data can be recovered from the snapshot file on the disk.
3. AOF: Append Redis write operations to a log file, so that when Redis restarts, data can be recovered by replaying the write operations from the log file. Configuring periodic rewriting of the AOF file can reduce its size.
4. Master-slave replication: Redis supports a master-slave replication mechanism, which allows the data from the master node to be synchronized to multiple slave nodes. In case of a failure or data loss on the master node, data can be retrieved from one of the slave nodes.
5. Redis Sentinel is a high availability solution for Redis that monitors the state of both the master and slave nodes, and automatically promotes a slave node to a new master node when the current master fails.
6. Redis Cluster is the distributed solution for Redis, which is capable of spreading data across multiple nodes to ensure availability and reliability through data replication and failover mechanisms.
7. Regularly back up data and store backup files in a secure location so that data can be recovered using the backup files in case of data loss.

By utilizing the mechanisms and methods mentioned above, the reliability and availability of Redis data can be significantly improved, thus reducing the risk of data loss.