Zookeeper (two) installation

Zookeeper (two) installation

Local mode installation

Preparation before installation

1. Install jdk

2. Copy apache-zookeeper-3.6.0-bin.tar.gz to the opt directory

3. Unzip the installation package

   tar -zxvf apache-zookeeper-3.6.0-bin.tar.gz
   

4. Rename

   mv apache-zookeeper-3.6.0-bin zookeeper
   

Configuration modification

Create the zkData and zkLog directories on the /opt/zookeeper/ directory

mkdir zkData
mkdir zkLog

Enter the path /opt/zookeeper/conf, copy a zoo_sample.cfg file and name it zoo.cfg

cp zoo_sample.cfg zoo.cfg

Edit the zoo.cfg file and modify the dataDir path

dataDir=/opt/zookeeper/zkData
dataLogDir=/opt/zookeeper/zkLog

Operate Zookeeper

Start Zookeeper

./zkServer.sh start

Check whether the process is started

jps

QuorumPeerMain: is the startup entry class of the zookeeper cluster, which is used to load the configuration to start the QuorumPeer thread

Check status

./zkServer.sh status

Start the client

./zkCli.sh

Exit the client

quit

Interpretation of configuration parameters

The meaning of the parameters in the zoo.cfg configuration file in Zookeeper is interpreted as follows:

• tickTime = 2000: the number of communication heartbeats, the heartbeat time between Zookeeper server and client, in milliseconds

  • The basic time used by Zookeeper is the time interval between servers or between the client and the server to maintain a heartbeat, that is, a heartbeat will be sent every tickTime, and the time unit is milliseconds.

• initLimit =10: LF initial communication time limit

  • The maximum number of heartbeats that can be tolerated at startup between the Follower server and Leader server in the cluster
  • 10*2000 (10 heartbeat time) If the leader and follower do not send out heartbeat communication, it is regarded as an invalid connection, and the leader and follower are completely disconnected

• syncLimit =5: LF synchronization communication time limit

  • After the cluster is started, the maximum response time unit between Leader and Follower. If the response exceeds syncLimit *tickTime->10 seconds, Leader thinks that the follower is dead and deletes the follower from the server list

• dataDir: data file directory + data persistence path

  • Mainly used to save data in Zookeeper.

• dataLogDir: log file directory

• clientPort =2181: client connection port

  • The port that listens for client connections.