1. Migrating from Another
Distribution
7/6/2012
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2. Migration
Agenda
• Migration Roadmap
• Planning the Migration
• MapR Deployment
• Component Migration
• Application Migration
• Data Migration
• Node Migration
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3. Migration
Objectives
At the end of this module you will be able to:
• List the important steps in migrating to MapR from another Hadoop
distribution
• Plan for a migration to MapR
• Describe the process for migrating components to MapR
• Identify the steps for migrating applications to MapR
• Explain how to migrate data to MapR
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4. Migration Roadmap
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5. Migration Roadmap
 Planning
 Initial MapR Deployment
 Component Migration
 Application Migration
 Data Migration
 Node Migration
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6. Planning the Migration
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7. Planning the Migration
 Requirements and goals
 Potential issues
 Data migration
– Move datasets individually or all at once?
 Downtime
– How much can you tolerate, if any?
 Customization
 Storage
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8. MapR Deployment
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9. MapR Deployment
 Install, configure and test MapR cluster
 Add ecosystem components and applications you need
 Test MapR functionality
– Your custom patches and one-off code might no longer be needed
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10. Component Migration
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11. Component Migration
 Hive Migration
– Import table schemas
– Import Hive metastore
– Using Hive with volumes
 HBase Migration
– Use the /hbase volume
– Turn off compression for the /hbase volume
 Migrating customized components
– Reapply your patches to MapR versions
– Do not hardcode paths – use fs.default.name
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12. Application Migration
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13. Application Migration
 Make sure Java classpath includes path to maprfs.jar
 Make sure java.library.path includes libMapRClient.so
 Use fs.default.name
– Point to maprfs:///
– Uses cluster specified on the first line of mapr-clusters.conf
 The distcp command does not copy file permissions
 Remove explicit memory settings from your application
 Test application with a small amount of data
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14. Data Migration
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15. Data Migration
 Distributed copy
– hadoop distcp command
– Sets up MapReduce job to copy files and directories
 Push data
– Use MapR File Client to push data from the other cluster
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16. Node Migration
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17. Node Migration
 Reclaim nodes
– Decommission nodes from the other cluster
– Make sure the nodes meet the MapR installation requirements
– Add the nodes to the MapR cluster
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18. Questions
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