A resilient cluster keeps the same Opensolr Index on three servers, one master and two replicas, so it keeps answering searches when one of them fails.
01 · How it works
One master takes the writes
Every update your app sends goes to the master. The two replicas copy it.
Searches are spread over the servers
Reads are kept apart from writes, and the load is shared.
One address for your app
Your app connects to the Host shown on the Info tab of the master. More: Clusters and replicas.
A watchdog keeps it running
The servers are checked all the time. A server that stops answering gets its services restarted automatically.
02 · Standalone or cluster
Standalone index
Made with Solr › Add New Index. It lives on one server. Enough for most sites, where a short break in search is acceptable.
Resilient cluster
Made with Solr › Add New Cluster. Three servers behind one address, for search that has to stay up under high traffic.
03 · What it costs
A cluster is one part of your plan. On the pricing page each cluster costs €25 a month, next to the indexes, disk and traffic of the plan, and your plan sets how many clusters you can have: What a plan is made of.
Servers only you use: Opensolr Enterprise, or Request Your Private Cluster Environment on the Add New Cluster page.
Compare the hosting tiers
Shared, shared cluster, dedicated and dedicated cluster, side by side.