This topic describes how to connect to ZooKeeper and view the information about ZooKeeper nodes (znodes) in the E-MapReduce (EMR) console.

Prerequisites

An EMR cluster is created, and ZooKeeper is selected from the optional services when you create the cluster. For more information, see Create a cluster.
Note You do not need to select ZooKeeper for a high-availability cluster because ZooKeeper is deployed in high-availability clusters by default.

For more information about ZooKeeper, see ZooKeeper Getting Started Guide.

Connect to ZooKeeper

You can use the command-line tool zkCli.sh to connect to ZooKeeper. zkCli.sh is in the /usr/lib/zookeeper-current/bin/ directory.

To connect to ZooKeeper, run the following command: 
/usr/lib/zookeeper-current/bin/zkCli.sh -server IP address/hostname:port

For more information about how to obtain the IP address and hostname, see View the information of znodes. port indicates the port number.

Example: 
/usr/lib/zookeeper-current/bin/zkCli.sh -server emr-header-1:2181
After you connect to ZooKeeper, you can use the /ls command to view the information about znodes.

View the information of znodes

  1. Go to the Cluster Overview page.
    1. Log on to the Alibaba Cloud EMR console.
    2. In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
    3. Click the Cluster Management tab.
    4. On the Cluster Management page, find your cluster and click Details in the Actions column.
  2. In the left-side navigation pane, choose Cluster Service > ZooKeeper.
  3. Click the Component Deployment tab.
    You can view the information about znodes.