Hi Mikhail, 1. Create an empty collection with the same number of shards as before 2. Set legacyCloud cluster property to true (it is false by default) using: ./server/scripts/cloud-scripts/zkcli.sh -zkhost 127.0.0.1:2181 -cmd clusterprop -name legacyCloud -val true 3. Bring your solr nodes back online, they should register themselves to ZK as they used to do in old versions of Solr
But as always in such cases, take snapshots of those persistent disks and test before you execute :) Also, be aware of this bug: https://issues.apache.org/jira/browse/SOLR-11503 when in future you want to turn off legacyCloud mode. Good luck! On Thu, Jun 18, 2020 at 1:06 PM Mikhail Khludnev <[email protected]> wrote: > Hello, > I'm challenged with cluster recovery. Think about total failure: ZK state > is lost, however instanceDirs survived since they are mounted via EBS. > Let's say collection is read/only and/or it doesn't have replicas, just > leaders. > Is there a way to create a new empty collection and say, hey here's shard1 > instance, shard2 instance is there etc? > > Customer says that the old version of solr does it automatically: when > empty zk is connected, collection's shards just appear there. Right now due > to https://issues.apache.org/jira/browse/SOLR-12066 Cleanup deleted core > when node start - if instances with data dirs connect to empty ZK it just > wipes dirs away. > > Thanks > -- > Sincerely yours > Mikhail Khludnev > -- Regards, Shalin Shekhar Mangar.
