Apache Solr Reference Guide Covering Apache Solr 6.0

Setting up a ZooKeeper Ensemble
With an external ZooKeeper ensemble, you need to set things up just a little more carefully as compared to the
Getting Started example.
The difference is that rather than simply starting up the servers, you need to configure them to know about and
talk to each other first. So your original zoo.cfg file might look like this:
dataDir=/var/lib/zookeeperdata/1
clientPort=2181
initLimit=5
syncLimit=2
server.1=localhost:2888:3888
server.2=localhost:2889:3889
server.3=localhost:2890:3890
Here you see three new parameters:
initLimit: Amount of time, in ticks, to allow followers to connect and sync to a leader. In this case, you have 5
ticks, each of which is 2000 milliseconds long, so the server will wait as long as 10 seconds to connect and sync
with the leader.
syncLimit: Amount of time, in ticks, to allow followers to sync with ZooKeeper. If followers fall too far behind a
leader, they will be dropped.
server.X: These are the IDs and locations of all servers in the ensemble, the ports on which they communicate
with each other. The server ID must additionally stored in the /myid file and be located in the dataD
ir of each ZooKeeper instance. The ID identifies each server, so in the case of this first instance, you would
create the file /var/lib/zookeeperdata/1/myid with the content "1".
Now, whereas with Solr you need to create entirely new directories to run multiple instances, all you need for a
new ZooKeeper instance, even if it's on the same machine for testing purposes, is a new configuration file. To
complete the example you'll create two more configuration files.
The /conf/zoo2.cfg file should have the content:
tickTime=2000
dataDir=c:/sw/zookeeperdata/2
clientPort=2182
initLimit=5
syncLimit=2
server.1=localhost:2888:3888
server.2=localhost:2889:3889
server.3=localhost:2890:3890
You'll also need to create /conf/zoo3.cfg:
tickTime=2000
dataDir=c:/sw/zookeeperdata/3
clientPort=2183
initLimit=5
syncLimit=2
server.1=localhost:2888:3888
server.2=localhost:2889:3889
server.3=localhost:2890:3890
Apache Solr Reference Guide 6.0
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