1. Hadoop
Edit by Cassell Hsu
2013.04.19

2. Hadoop
Master
Slave
Slave
Slave

3. Hadoop
• Master
• NameNode
• JobTracker
• SecondaryNameNode

4. NameNode
• Where is NameNode?
• Master
• HDFS(Hadoop Distributed File System)
• What is NameNode?
• 資料之位置資訊
• 資料之屬性
？？

5. NameNode
• 位置資訊 ?
• 所有資料皆存放在 – DataNode

6. DataNode
• What is DataNode
• 存放資料
• Where is DataNode
• HDFS
• Slaves (and Master)

7. UserUser
DataNodeDataNode
NameNodeNameNode
DataNodeDataNode
DataNodeDataNode
128
Mb B
64Mb
A
64Mb
Check hdfs-site.xml
B
64Mb
A
64Mb

8. Hadoop
DataNodeDataNodeNameNodeNameNode
Master
DataNodeDataNode
DataNodeDataNode
DataNodeDataNode
Slaves

9. Hadoop
• Master
• NameNode
• JobTracker
• SecondaryNameNode

10. JobTracker
• What is JobTracker?
• 排程工作
• Where is JobTracker?
• Master
誰來工作？

11. JobTracker & TaskTracker
JobTracker TaskTracker
Where Master Slaves
What 排程工作 執行工作

12. Hadoop
DataNodeDataNodeNameNodeNameNode
Master
DataNodeDataNode
Slaves
JobTrackerJobTracker
TaskTrackerTaskTracker

13. Hadoop
• Master
• NameNode
• JobTracker
• SecondaryNameNode

14. SecondaryNameNode
• What is SecondaryNameNode?
• NameNode 發生錯誤時補救
• Where is SecondaryNameNode?
• Master

15. Hadoop
DataNodeDataNodeNameNodeNameNode
Master
DataNodeDataNode
Slaves
JobTrackerJobTracker
TaskTrackerTaskTracker
SecondaryNodeSecondaryNode

16. MapReduce
User Master
Slave2
Slave1
A
A1
A2
Task
NameNode
Task
Result1
Result2
Reduce
Final ResultHDFS

17. MapReduce
• 案切割檔
• Hadoop 上區塊切割
• 程式指定