hdp zookeeper #1
Description
Hortonworks ZooKeeper is a centralized, reliable, service for maintaining configuration information, naming, providing distributed synchronization, and group services. All of these kinds of services are used in some form or another by distributed applications. In order to install and configure Hortonworks HBase and other Hadoop ecosystem components, you must start the ZooKeeper service.
- Tags:
- applications ›
Hortonworks zookeeper for HDP 2.1
ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. All of these kinds of services are used in some form or another by distributed applications. Each time they are implemented there is a lot of work that goes into fixing the bugs and race conditions that are inevitable.
Because of the difficulty of implementing these kinds of services, applications initially usually skimp on them ,which make them brittle in the presence of change and difficult to manage. Even when done correctly, different implementations of these services lead to management complexity when the applications are deployed.
To learn more about ZooKeeper visit the upstream docs
Deployment Strategy
Instruction to create a zookeeper node :
juju deploy hdp-zookeeper hdp-zookeeper
Step by step instructions to create a zookeeper quorum :
juju deploy hdp-zookeeper hdp-zookeeper
juju add-unit -n 2 hdp-zookeeper
How to integrate zookeeper into a your solution
add a relation file 1) Add relation metadata.yaml requires: zookeeper: interface: zookeeper
2) Add zookeeper-relation-changed hook, example: def zookeeper_relation_changed(): log('zookeeper-relation-changed called') ZK_hostname = relation_get('private-address') if not ZK_hostname: sys.exit(0)
Caveats
The config option for zookeeper_data_dir is only set'able at deployment time. If you update this value post deployment it no-op's, as it would be destructive.
Charmer Contact Information
amir sanjar amir.sanjar@canonical.com
zookeeper Upstream Project Name
Configuration
- zk-port
- (int) ZooKeeper Client Access Port
- 2181
- zookeeper_data_dir
- (string) Directory where ZooKeeper will store data.
- /grid/hadoop/zookeeper/data