bq: I was envisioning a scenario where the entire solr home is on the old volume that's going away. If I were setting up a Solr install where the large/fast storage was a separate filesystem, I would put the solr home (or possibly even the entire install) under that mount point. It would be a lot easier than setting dataDir in core.properties for every core, especially in a cloud install.
Agreed. Nothing in what I said precludes this. If you don't specify dataDir, then the index for a new replica goes in the default place, i.e. under your install directory usually. In your case under your new mount point. I usually don't recommend trying to take control of where dataDir points, just let it default. I only mentioned it so you'd be aware it exists. So if your new install is associated with a bigger/better/larger EBS it's all automatic. bq: If the dataDir property is already in use to relocate index data, then ADDREPLICA and DELETEREPLICA would be a great way to go. I would not expect most SolrCloud users to use that method. I really don't understand this. Each Solr replica has an associated dataDir whether you specified it or not (the default is relative to the core.properties file). ADDREPLICA creates a new replica in a new place, initially the data directory and index are empty. The new replica goes into recovery and uses the standard replication process to copy the index via HTTP from a healthy replica and write it to its data directory. Once that's done, the replica becomes live. There's nothing about dataDir already being in use here at all. When you start Solr there's the default place Solr expects to find the replicas. This is not necessarily where Solr is executing from, see the "-s" option in bin/solr start -s..... If you're talking about using dataDir to point to an existing index, yes that would be a problem and not something I meant to imply at all. Why wouldn't most SolrCloud users use ADDREPLICA/DELTEREPLICA? It's commonly used to more replicas around a cluster. Best, Erick On Fri, Aug 4, 2017 at 11:15 AM, Shawn Heisey <apa...@elyograg.org> wrote: > On 8/2/2017 9:17 AM, Erick Erickson wrote: >> Not entirely sure about AWS intricacies, but getting a new replica to >> use a particular index directory in the general case is just >> specifying dataDir=some_directory on the ADDREPLICA command. The index >> just needs an HTTP connection (uses the old replication process) so >> nothing huge there. Then DELETEREPLICA for the old one. There's >> nothing that ZK has to know about to make this work, it's all local to >> the Solr instance. > > I was envisioning a scenario where the entire solr home is on the old > volume that's going away. If I were setting up a Solr install where the > large/fast storage was a separate filesystem, I would put the solr home > (or possibly even the entire install) under that mount point. It would > be a lot easier than setting dataDir in core.properties for every core, > especially in a cloud install. > > If the dataDir property is already in use to relocate index data, then > ADDREPLICA and DELETEREPLICA would be a great way to go. I would not > expect most SolrCloud users to use that method. > > Thanks, > Shawn >
