Temporal High Availability - Interactive Demo
What is Temporal High Availability?
Temporal Cloud High Availability gives every Namespace a synchronized replica — a standby that can take over in under 20 minutes, with less than 1 minute of data loss, regardless of whether an availability zone, an entire region, or a whole cloud provider fails.
The core idea in one sentence
Your Namespace asynchronously replicates all Workflow history to a replica in a separate isolation domain — so if the primary fails, Temporal promotes the replica and your Workflows keep running with minimal data loss.
The Problem HA Solves
Single isolation domain
Standard Namespaces replicate across three availability zones in one region, handling AZ-level failures automatically. But a cell-level bug, a regional outage, or a cloud-provider incident can take your Namespace offline with no automatic recovery path. Backups run every 4 hours — meaning hours of potential data loss.
Active primary + synchronized replica
Every Workflow Execution is asynchronously replicated to a replica in a separate isolation domain. Temporal Cloud continuously monitors health and automatically fails over to the replica — restoring service within the RTO window with sub-1-minute data loss.
What It Looks Like
Standard vs. High Availability
| Metric | Standard Namespace | HA Namespace |
|---|---|---|
| Uptime SLA | 99.9% | 99.99% |
| AZ-level failure | ✓ Automatic (zero RPO) | ✓ Automatic (zero RPO) |
| Cell / regional failure RPO | Up to 4 hours (backup) | < 1 minute |
| Cell / regional failure RTO | Manual intervention | 20 minutes |
| Automatic failover | ✗ | ✓ Temporal-initiated (default) |
| Replication lag (p95) | N/A | < 1 minute |