How-To: Cleanup SolrCloud entries in ZooKeeper

[#1]

These instructions assume you don't need to preserve Solr indexes. If you do, modify ZK commands to move nodes instead of removing them.

Stop every SolrCloud node:

# on every SolrCloud node
su - solr
cd /opt/lucidworks-hdpsearch/solr/bin/
./solr stop -all

Connect to your ZooKeeper quorum and run zkCli shell:

su - zookeeper
cd /usr/hdp/current/zookeeper-client/bin/

# point it to a ZK quorum (or just a single ZK server is ok, e.g. localhost)
./zkCli.sh -server lake02:2181,lake03:2181,lake04:2181

If you followed best practices and chroot'ed your SolrCloud already, then things are easy (and you probably are done by now):

# in ZK cli shell
rmr /solr

More often this wasn't the case, so perform the following operations on your ZK tree:

# in ZK cli shell
rmr /clusterstate.json
rmr /aliases.json
rmr /live_nodes
rmr /overseer
rmr /overseer_elect
rmr /collections

Next, follow this best practices article, create a new ZK home for your SolrCloud cluster and start it up in chroot'ed mode.

[#2]

Nice article ..

Is there a way to delete a particular collection from Zookeeper using rmr or other command ?

we have a situation where the deleted collections from SOLR was gone but it is still in Zookeeper..

Cheers

K

[#3]

If you execute "rmr /solr". you may encounter following authentication error.

rmr /solr

Authentication is not valid : /solr/security

To workaround this you can use skipACL option, which found in the following site.

https://www.programmersought.com/article/60861634876/

Note: This is workaround steps in Cloudera Manager. 

1. Zookeeper->Configration->java Configuration Options for Zookeeper Server Add -Dzookeeper.skipACL=yes

2. Restart the zookeeper service

Remember to revert the change and restart zookeeper after you manage to remove /solr

rgds,

Rama.