Ignition SCADA Redundancy Setup Guide
Key Takeaway
A practical guide to Ignition SCADA redundancy architecture — covering master/backup gateway configuration, automatic failover, network requirements, testing procedures, and common pitfalls.
Quick Answer
Ignition redundancy uses a master/backup gateway architecture where the backup continuously mirrors the master's configuration, tags, and projects. During a failover event, the backup gateway automatically assumes control with minimal disruption. Proper redundancy setup requires matching Ignition versions, dedicated network connectivity, and regular failover testing to validate recovery behavior.
How Ignition Redundancy Works
Ignition by Inductive Automation supports built-in redundancy through its gateway network. A backup gateway maintains a real-time copy of the master's project resources, tag configuration, alarm states, and historical data pointers. When the backup detects that the master is unresponsive, it automatically promotes itself to master and assumes all client connections and OPC/database connections.
This differs from cold standby approaches used by some legacy SCADA platforms. Ignition's hot standby model means failover typically completes in seconds rather than minutes, with client sessions reconnecting automatically.
Architecture Requirements
- Matching Ignition versions — master and backup must run the same Ignition version and module set
- Dedicated redundancy network — a separate NIC or VLAN for master/backup communication is recommended
- Shared database access — both gateways need connectivity to the same historian database(s)
- License configuration — redundancy requires specific license activation on both gateways
- Firewall rules — ports 8060 (Gateway Network SSL, used for redundancy) and 8043/8088 (gateway web interface) must be open between servers
Step-by-Step Configuration
- Install Ignition on both servers with identical module sets
- Configure the master gateway's redundancy settings (Gateway Config → Redundancy)
- Set the backup gateway to point at the master's address
- Verify project synchronization completes (check gateway status page)
- Test a manual failover from the gateway web interface
- Validate that clients reconnect and historical data continues logging
Failover Testing Best Practices
NFM's managed Ignition SCADA services include scheduled failover drills. These tests verify that the backup gateway assumes control cleanly, client sessions reconnect without operator intervention, historian data continuity is maintained, and alarm states transfer correctly. Testing should occur quarterly at minimum and after any major configuration change.
Common Pitfalls
| Issue | Cause | Resolution |
|---|---|---|
| Backup stays inactive after master failure | Network firewall blocking port 8060 (Gateway Network SSL) | Open Gateway Network and web ports between gateways |
| Historian gap during failover | Backup lacks database connectivity | Verify both gateways can reach historian DB |
| Client connection timeout | DNS resolution delay | Use IP addresses or low-TTL DNS entries |
| Module mismatch errors | Version drift between master and backup | Always upgrade both gateways simultaneously |
Frequently Asked Questions
Ignition's hot standby failover typically completes in 5–30 seconds depending on the number of connected devices and clients. Client sessions reconnect automatically without operator intervention in most configurations.
Yes. Both the master and backup gateways require Ignition licenses with redundancy enabled. The backup license is typically less expensive than the master license. Contact Inductive Automation for current redundancy license pricing.
NFM recommends quarterly failover testing at minimum, plus additional tests after major configuration changes, Ignition version upgrades, or infrastructure modifications. Regular testing catches configuration drift before it becomes a production issue.