[HADOOP-7030] Add TableMapping topology implementation to read host to rack mapping from a file

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20.1, 0.20.2, 0.21.0
• Fix Version/s: 2.0.0-alpha
• Target Version/s: 1.2.0, 0.23.3
• Hadoop Flags: Reviewed
• Assignee: Thomas White
• Reporter: Patrick Angeles
• Created: 12/Nov/10 05:08
• Updated: 20/Nov/12 21:47
• Resolved: 23/Mar/12 21:08

Description

The default ScriptBasedMapping implementation of DNSToSwitchMapping for determining cluster topology has some drawbacks. Principally, it forks to an OS-specific script.

This issue proposes two new Java implementations of DNSToSwitchMapping. TableMapping reads a two column text file that maps an IP or hostname to a rack ID. Ip4RangeMapping reads a three column text file where each line represents a start and end IP range plus a rack ID.

Issue Links

• is duplicated by: HADOOP-8091 Add a topology mapper that reads hostname to rack mappings from a Java properties file
• is related to: HADOOP-8628 TableMapping init sets initialized flag prematurely
• is related to: HADOOP-8631 The description of net.topology.table.file.name in core-default.xml is misleading
• is related to: HADOOP-8091 Add a topology mapper that reads hostname to rack mappings from a Java properties file
• is related to: HADOOP-8231 Make topologies easier to set up and debug
• is related to: HADOOP-8629 Add option for TableMapping to reload mapping file on match failure
• relates to: HADOOP-7423 Document topology script requirements