THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
Design details and discussion for KNOX-88
Definition
Knox HA is a set of routines for transparent work with Hadoop service that stands in HA mode.
Purpose of Knox HA service
- Automatic failover. (Example: switch request from not responding name-node to active name-node.)
- Pluggable support of failover strategies.
- Daemon-service for regular ping of Hadoop service state (Performance optimization to keeping actual state of service).
Topology
<topology> <gateway> ... <provider> <role>ha</role> <name>HAProvider</name> <param> <name>webhdfs.ha</name> <value>failover_strategy=BaseStrategy;retryCount=3;timeoutInterval=5000;enabled=true</value> </param> </provider> ... <gateway> ... <service> <role>WEBHDFS</role> <url>machine1.example.com:50070</url> <url>machine2.example.com:50070</url> </service> ... <service> <role>NAMENODE</role> <url>machine1.example.com:50070</url> <url>machine2.example.com:50070</url> </service> ... </topology>
Example UML
Example Code Block
Code Title
class X { }