Install a highly available Redis deployment

To provide high availability and data persistence, Mirantis Secure Registry (MSR) 4 supports external Redis configurations. During deployment, select one of the following high-availability architectures for the Redis backend:

• Redis-only (replication) deployment
• Redis with Sentinel deployment

Redis-only (Standard Replication)

In this mode, MSR 4 connects to a Redis cluster configured with a master-replica relationship. Data is written to the master node and asynchronously replicated to one or more replicas.

Use this setup for development or staging environments that require data redundancy but can tolerate a short manual-intervention window for failover.

This setup does not include automatic failover. If the master node goes down, MSR 4 loses write capability until a replica is manually promoted to master or the master node is restored.

Redis with Sentinel

In this mode, MSR 4 is Sentinel-aware. Instead of connecting to a fixed IP address, it queries the Sentinel nodes to resolve the current master.

Use this setup for production environments where maximum uptime and automatic recovery are required. This mode adds a monitoring layer to the standard Redis replication setup.

Sentinel nodes continuously monitor the Redis master and replicas and use a quorum-based vote to determine whether the master has failed. If the master fails, the Sentinels automatically initiate a failover process: they elect a new master from the available replicas and notify MSR 4 of the new address.