Question - How do I delete ZooKeeper data?

Answered by: Willie Adams  |  Category: General  |  Last Updated: 07-09-2021  |  Views: 1147  |  Total Questions: 13

Stop Zookeeper. Go to the bin folder of your Zookeeper. Run. /zkCli. sh. Use ls / to check Zookeeper's content. Identify what you want to delete with the exact path. Delete /znode or path of what you want to delete. ZooKeeper stores its data in a data directory and its transaction log in a transaction log directory. By default these two directories are the same. The server can (and should) be configured to store the transaction log files in a separate directory than the data files. Zookeeper Metrics Amount of time it takes for the server to respond to a client request (since the server was started). Number of queued requests in the server. This goes up when the server receives more requests than it can process. When count > 10. Update zoo. cfg for all existing Zookeeper nodes to remove the entry for the node. Restart all Zookeeper nodes. Update solrserver. properties of all the Solr nodes to remove the Zookeeper node: Restart all Solr nodes. Update wt. properties to remove the Zookeeper node: Restart Windchill. The odd number of servers allows ZooKeeper to perform majority elections for leadership. At any given time, there can be up to n failed servers in an ensemble and the ZooKeeper cluster will keep quorum. If at any time, quorum is lost, the ZooKeeper cluster will go down.

Zookeeper is registry for large distributed systems. It is beneficial for tasks like master election, crash detection and managing meta data related to distributed systems. In simple terms, load balancer helps in distribution of workload across multiple servers.

Apache ZooKeeper is used for maintaining centralized configuration information, naming, providing distributed synchronization, and providing group services in a simple interface so that we don't have to write it from scratch. Apache Kafka also uses ZooKeeper to manage configuration.

Zookeeper process runs on infra VM's. To start the zookeeper service use command: /usr/share/zookeeper/bin/zkServer. sh start. To check whether process is running: ps -ef | grep zookeeper. Errorlogs can be checked in Infra nodes: /var/log/zookeeper/zookeeper. log. Check the free memory: free -mh.

How Apache ZooKeeper Works Internally. When the client doesn't receive an acknowledgment from the server within the specified time, the client connects to another server in the ensemble, and the client session is transparently transferred over to the new ZooKeeper server.

Every node in a ZooKeeper tree is refered to as a znode. Znodes maintain a stat structure that includes version numbers for data changes, acl changes. The stat structure also has timestamps. The version number, together with the timestamp allow ZooKeeper to validate the cache and to coordinate updates.

You need a minimum of 3 zookeepers nodes and 2 Kafka brokers to have a proper fault tolerant cluster. Recommended minimum fault tolerant cluster would be 3 Kafka brokers and 3 zookeeper nodes with replication factor = 3 on all topics.

But in production, you should run ZooKeeper in replicated mode. A replicated group of servers in the same application is called a quorum, and in replicated mode, all servers in the quorum have copies of the same configuration file.

Stop Zookeeper. Go to the bin folder of your Zookeeper. Run. /zkCli. sh. Use ls / to check Zookeeper's content. Identify what you want to delete with the exact path. Delete /znode or path of what you want to delete.

Kafka 0. 9 can run without Zookeeper after all Zookeeper brokers are down. After killing all three Zookeeper nodes the Kafka cluster continues functioning.

As explained by others, Kafka (even in most recent version) will not work without Zookeeper. Kafka uses Zookeeper for the following: Electing a controller. The controller is one of the brokers and is responsible for maintaining the leader/follower relationship for all the partitions.

Kafka uses Zookeeper to manage service discovery for Kafka Brokers that form the cluster. Zookeeper sends changes of the topology to Kafka, so each node in the cluster knows when a new broker joined, a Broker died, a topic was removed or a topic was added, etc.

Architecture. Kafka is distributed as in the sense that it stores, receives and sends records on different nodes (called brokers). Brokers receive records from producers, assigns offsets to them, and commits them to storage on disk. To run Kafka, you need Zookeeper.

With kafka 0. 9+ the new Consumer API was introduced. New consumers do not need connection to Zookeeper since group balancing is provided by kafka itself.