SolrCloud ZooKeeper compatibility

2
votes

We have Solr running in our production environment in a master-slave setup which works great. But we are looking to shore up our Solr infrastructure more as we get Solr involved more involved in our solution.

For this, we are looking to implement SolrCloud. I have gone through the documentation of SolrCloud and it seems straight enough to implement.

One area, where I'm not clear, where I need more information is what version of ZooKeeper goes with a specific version of Solr in SolrCloud. I'm looking to go with Solr 5.5 for SolrCloud, due to supported compatibility with another product we use here. Is there a compatibility chart that I can look at to determine the appropriate version of ZooKeeper?

2
solrapache-zookeepersolrcloud

2 Answers

2
votes

I'm fairly sure the Zookeeper protocol has been kept stable between the versions used by Solr, so that shouldn't really be an issue (the 3.4.x version has been in use for many years now).

The only important part I remember is that Solr itself changed how it expects the layout of the zookeeper store to be - moving from a global clusterstate.json to a state.json for each collection. This helps immensely with scalability and the need to push all updates to all nodes. That scale might not have much relevancy for you at this time, however.

However, to find the exact version used in a version of Solr, CHANGES.txt can be helpful! For the last version of Solr 5.5, this was the bundled versions:

Versions of Major Components
---------------------
Apache Tika 1.7
Carrot2 3.10.4
Velocity 1.7 and Velocity Tools 2.0
Apache UIMA 2.3.1
Apache ZooKeeper 3.4.6
Jetty 9.2.13.v20150730
1
votes

Our kerberized Hadoop cluster has running Solr 5.5 on three nodes. We are using ZooKeeper 3.4.6. This works like a charm. However ZK config changes can be a pain in the ass sometimes and has to be done with caution in a production environment. Are you using Kerberos? Than ZK setup is a little different.