What Is a Resilient Cluster?
A Resilient Cluster is a high-availability Solr setup where your data lives on multiple dedicated servers simultaneously. If one server goes down, the others keep serving your queries without interruption. Your users never notice a thing.
The architecture is straightforward: one master handles all writes, and multiple replicas continuously sync from it and serve read queries. A load balancer sits in front and distributes traffic. If the master goes down, a replica takes over automatically.
How Is This Different From a Standalone Index?
Think of it this way: a standalone index is a single road to your data. A resilient cluster is multiple highways — if one is blocked, traffic flows through the others without anyone noticing.
What Comes With a Resilient Cluster?
How Does Billing Work?
The Resilient Cluster is priced as a single monthly fee that covers the entire cluster — master, replicas, load balancer, replication, monitoring, and support. You don't pay per server or per query.
Resilient Cluster plans start at €25/month for plug-and-play shared clusters, and go up to fully dedicated enterprise environments. See the full breakdown on the Enterprise Solr Cloud page or the Pricing page.
What Happens During a Server Failure?
Here's exactly what happens if one of the servers in your cluster goes down:
- A server goes down (hardware failure, network issue, maintenance)
- The watchdog detects the failure within seconds
- Traffic is rerouted to the remaining healthy nodes
- Your users continue searching without interruption
- The failed server is automatically recovered and re-synced
Your search never goes offline. That's the entire point.
Who Needs a Resilient Cluster?
Not everyone does — and that's fine. Here's a simple way to decide:
— Your traffic is moderate and predictable
— Search is important but not mission-critical
— You want the lowest cost option
— You serve high-traffic production search
— Your application depends on 24/7 availability
— You need redundancy and automatic failover