Database High Availability: One Specialist for Your Entire Database Tier
JusDB architects and implements high availability across MySQL, PostgreSQL, MongoDB, Cassandra, SQL Server, and MariaDB — multi-AZ failover, multi-region active-active replication, cloud-native HA patterns, and automated runbook execution so your databases never become the single point of failure.
Need HA for a single database engine? Jump to the database-specific HA implementation guide: PostgreSQL HA → MySQL HA → MongoDB HA →
Why You Need a Multi-Database HA Specialist
Modern applications rarely run on a single database engine. The team that builds your MySQL HA topology may not understand Cassandra multi-DC replication — or MongoDB replica set elections. A specialist in only one database leaves the rest of your stack exposed.
6 Database Engines
MySQL, PostgreSQL, MongoDB, Cassandra, SQL Server, and MariaDB — JusDB architects HA for all of them, with deep knowledge of each engine's unique failover mechanics and replication semantics.
Multi-Region Active-Active
Design globally distributed topologies where writes are accepted in multiple regions simultaneously. Includes conflict resolution strategy, latency budgets, and regional failure isolation.
Cloud-Native HA Patterns
Multi-AZ deployments on AWS, GCP, and Azure. Leverage managed services (RDS Multi-AZ, Cloud SQL HA, Atlas Global Clusters) where appropriate, self-managed where control is required.
Automated Failover & Runbooks
Failover must be automatic — human-initiated failover during an incident adds 5–15 minutes of downtime. JusDB implements and validates fully automated failover with runbook execution via Rundeck or custom operators.
Chaos Engineering Validation
HA that has not been tested is not HA. JusDB runs systematic failure injection — node kills, network partitions, AZ failures — to verify actual RTO and RPO against your SLOs before a real incident.
AI Anomaly Detection
Detect replication lag, connection saturation, and disk pressure before they cause a failover. JusDB integrates anomaly detection on top of your Prometheus/Grafana stack to give pre-incident warning.
HA Patterns: Which One Fits Your Workload?
The right HA pattern depends on your RTO requirement, RPO requirement, write volume, and geographic distribution. JusDB maps your SLOs to the appropriate architecture — not the other way around.
| HA Pattern | Description | RTO | RPO | Best For |
|---|---|---|---|---|
| Multi-AZ Active-Passive | Primary in one AZ, synchronous replica in a second AZ. Automatic failover in 20–60 seconds. Suited for OLTP workloads where RPO must be zero and RTO under 1 minute. | 20–60 s | 0 | MySQLPostgreSQLSQL Server |
| Multi-Region Active-Active | Writes accepted in multiple regions simultaneously. Requires conflict resolution strategy (last-write-wins or CRDTs). Ideal for globally distributed user bases with latency SLOs. | 0 (no failover) | 0 | CassandraCockroachDBMongoDB |
| Read Replica Scaling + HA | One primary handles writes; multiple read replicas serve reads. Replica promotion to primary on failure. Useful when read traffic is 80%+ of total load. | 30–120 s | Seconds | MySQLPostgreSQLMongoDB |
| Galera / Group Replication | Synchronous multi-primary replication. Any node accepts writes; quorum-based certification. Ideal for multi-master write requirements without global distribution. | < 10 s | 0 | MySQLMariaDB |
HA Tool Stack by Database
Each database engine has its own HA ecosystem. JusDB selects and implements the right tools for your engine, your cloud provider, and your RTO/RPO requirements.
MySQL HA Stack
MySQL specialist page- Orchestrator (topology management)
- Group Replication / Galera
- ProxySQL (R/W split + failover)
- MHA (Master HA)
PostgreSQL HA Stack
PostgreSQL specialist page- Patroni (etcd/Consul DCS)
- repmgr (lightweight replication)
- PgBouncer / pgPool-II (pooling)
- pgBackRest (PITR)
MongoDB HA Stack
MongoDB specialist page- Replica sets (3-node minimum)
- Sharded cluster topology
- Mongos routing layer
- Atlas Global Clusters
Cassandra HA Stack
Cassandra specialist page- Multi-DC replication (NetworkTopologyStrategy)
- Gossip protocol failure detection
- Read repair + hinted handoff
- Nodetool monitoring
MySQL / MariaDB HA Stack
MySQL / MariaDB specialist page- MaxScale (intelligent routing)
- Galera Cluster
- GTID-based replication
- Semi-sync replication
SQL Server HA Stack
SQL Server specialist page- Always On Availability Groups
- Failover Cluster Instances (FCI)
- Database Mirroring (legacy)
- Log Shipping
Cloud Provider HA: Managed vs Self-Managed
When to use Managed HA
Managed database services (RDS Multi-AZ, Cloud SQL HA, Atlas) handle failover mechanics but abstract away control. Use when:
- RTO of 1–2 minutes is acceptable
- Team lacks DBA capacity to manage replication
- Engine is standard (MySQL 8.0, PostgreSQL 15) with no exotic extensions
- Cloud vendor lock-in is acceptable for the workload
- Automated backups and PITR are required with minimal ops burden
When to use Self-Managed HA
Self-managed HA (Patroni, Orchestrator, Cassandra multi-DC) gives full control over failover timing and topology. Use when:
- RTO of under 20 seconds is required
- Multi-cloud or hybrid cloud topology (AWS + GCP + on-prem)
- Custom extensions or configurations not supported by managed services
- Need to control replication topology (cross-region routing, selective replication)
- Cost at scale makes managed services prohibitive (>$50k/month DB spend)
FAQ
Make your entire database tier resilient — not just one engine
JusDB reviews your current HA topology, identifies single points of failure, designs the right HA pattern for each database, and validates it with chaos engineering before it ever matters in production.