Hi Everyone, After Solr 7.0 we support a master slave architecture in SolrCloud. I'd expect more SolrJ support and follow up tasks as more people start using it.
Single node standalone Solr: You don't need to maintain a separate ZK ensemble and can use the embedded ZK since it's just one node of Solr . The only difference here would be the user having to upload configs to ZK rather than residing on local disk. We already have "bin/solr zk" to make this convenient and could enhance it more to make the transition smoother. Master-Slave setup: There can only be one master so an embedded ZK will work here as well. Again interacting with ZK for configs and not the local file system. They would create collections instead of cores and use pull replicas for slaves. What are the possible benefits ? 1. Consistent terminology : There will only be one way of running Solr . 2. Cores become an underlying implementation and from we can start calling them replicas . Today SolrCloud users need to understand what cores are , can manipulate them through core api's 3. Simpler setups : Today users have all sorts of ways of setting up solr . Have an instance directory , data directory , solr home. In a SolrCloud only world there would be ZK for configs and a data directory for indexes. For a new user coming in today what will be reasons that he doesn't use SolrCloud ? If there is still a wide gap then we can punt this to a later timeframe .
