Availability and reliability
AnalyticDB for PostgreSQL protects your data and keeps instances running through three complementary layers: dual-replica compute redundancy, triple-replica disk storage, and remote backup. Each layer addresses a different class of failure — from a single node crashing to a full data center outage.
| Failure scenario | Protection mechanism |
|---|---|
| Single compute node failure | Dual-replica primary/secondary architecture |
| Individual disk failure | Triple-replica (triple-modular redundancy) disk storage |
| Data center outage or accidental deletion | Remote backup and restoration |
How it works
AnalyticDB for PostgreSQL is a distributed database built on a massively parallel processing (MPP) architecture. Distributing workloads across compute nodes improves query performance, but also increases the probability of individual node failures. The following mechanisms address this at each layer of the stack.
Dual-replica compute redundancy
Each instance runs a primary/secondary architecture with two replicas per compute node. If a single replica set has at least one available compute node, the instance continues serving queries normally. This covers the most common failure scenario: a single node going offline.
Triple-replica disk storage
Each data file is stored across three independent disks in a triple-modular redundancy configuration. This prevents data loss from individual disk failures, independent of compute-level redundancy.
Remote backup
For data center-level failures or accidental data deletion — scenarios where local redundancy is not sufficient — AnalyticDB for PostgreSQL stores remote backups that you can use to restore your instance.
Automatic failover and recovery
AnalyticDB for PostgreSQL monitors the health status of every node in real time. When the primary compute node becomes unavailable, a hot standby node takes over automatically, keeping the instance available without manual intervention.
After a node failure, the system recovers the node to restore full multi-replica redundancy. The recovery method depends on the root cause:
| Root cause | Recovery action |
|---|---|
| Physical machine failure | Migrate the affected compute nodes to another physical machine |
| Suspended process | Restart the process |
Backup and restoration
Remote backup protects against data center-level failures and accidental data deletion.
Supported backup types
| Backup type | Status | Impact on running workloads |
|---|---|---|
| Full logical backup | Available | — |
| Incremental backup | Coming soon | No data locking; minimal impact |
Incremental backup, once available, will complement full logical backup by reducing disruption to running workloads.
Restoration granularity
Restore data at the granularity that matches your situation:
| Granularity | Description |
|---|---|
| Instance | Restore the entire instance from a backup |
| Database | Restore a specific database within an instance |
| Schema | Restore a specific schema within a database |