Based on the stand-alone version, DCS Redis active/standby instances have standby nodes to ensure the HA of services and data reliability. The deployment architecture adopts an active/standby dual-node mode, where the active node provides daily service access, and the standby node provides high data availability. When the active node fails and becomes unavailable, the system automatically switches to the standby node within seconds to ensure service continuity.
Architecture Diagram
Architecture Description
An active/standby instance includes two nodes: master and replica. Data persistence is enabled and data is synchronized among nodes.
DCS detects instance availability in real time. When the active node fails, the standby node takes over services from the active node.
Features
Data Synchronization
Maintains data consistency between the active and standby nodes of the DCS instance through incremental data synchronization. When a node fails, the active and standby instances perform a full-data synchronization after recovery from the fault to maintain data consistency.
Automatic Active/Standby Switchover Within Seconds
When the active node fails and becomes unavailable, the system automatically switches to the standby node within 30 seconds. The standby node is then upgraded to the active to restore data access without user operations, thus ensuring service continuity.
Multi-AZ Deployment
Supports multi-AZ deployment upon activation of an instance. The active and standby nodes can be deployed in different AZs. The power and network among nodes are physically isolated. When one of the AZs is unavailable, nodes in the other AZs can continue to provide services, avoiding service unavailability due to single-node faults and further improving data reliability.
Application Scenarios
Scenarios with High Redis Protocol Compatibility Requirements
The standard active/standby instances are fully compatible with the Redis protocol for smooth business migration.
Scenarios with Low Performance Pressure and HA Requirements
Due to the single-threaded mechanism of Redis, the standard version is not suitable for scenarios with large QPS. If the performance is within 100,000 QPS and there are certain requirements for high data availability, the standard active/standby version is suitable.