[
https://issues.apache.org/jira/browse/HADOOP-8232?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13242555#comment-13242555
]
Steve Loughran commented on HADOOP-8232:
----------------------------------------
Test output when a configuration is loaded that lists a map class that does not
load
{code}
bash hadoop-dist/target/hadoop-3.0.0-SNAPSHOT/bin/hadoop --config
/Users/slo/Java/Hadoop/github/hadoop-patches/misc/topology/invalid-mapper
org.apache.hadoop.net.TopologyTool testfile
/Users/slo/Java/Hadoop/github/hadoop-patches/misc/topology/hosts.txt
net.topology.node.switch.mapping.impl=org.apache.hadoop.net.ThisMappingClassIsNotDefined
2012-03-30 18:12:56,225 ERROR net.TopologyTool (TopologyTool.java:run(77)) -
Failed to load the DNS mapping
org.apache.hadoop.net.ThisMappingClassIsNotDefined: java.lang.RuntimeException:
java.lang.RuntimeException: java.lang.ClassNotFoundException: Class
org.apache.hadoop.net.ThisMappingClassIsNotDefined not found
java.lang.RuntimeException: java.lang.RuntimeException:
java.lang.ClassNotFoundException: Class
org.apache.hadoop.net.ThisMappingClassIsNotDefined not found
at
org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1298)
at
org.apache.hadoop.net.AbstractDNSToSwitchMapping.createCachingDNSToSwitchMapping(AbstractDNSToSwitchMapping.java:166)
at org.apache.hadoop.net.TopologyTool.run(TopologyTool.java:73)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
at org.apache.hadoop.net.TopologyTool.main(TopologyTool.java:228)
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: Class
org.apache.hadoop.net.ThisMappingClassIsNotDefined not found
at
org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1266)
at
org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1290)
... 5 more
Caused by: java.lang.ClassNotFoundException: Class
org.apache.hadoop.net.ThisMappingClassIsNotDefined not found
at
org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:1175)
at
org.apache.hadoop.conf.Configuration.getClass(Configuration.java:1264)
... 6 more
2012-03-30 18:12:56,229 ERROR net.TopologyTool (TopologyTool.java:run(79)) -
The configuration option is wrong, or the classpath is incomplete
{code}
The error message attempts to hint at the likely causes.
> Provide a command line entry point to view/test topology options
> ----------------------------------------------------------------
>
> Key: HADOOP-8232
> URL: https://issues.apache.org/jira/browse/HADOOP-8232
> Project: Hadoop Common
> Issue Type: Sub-task
> Components: util
> Affects Versions: 0.23.1
> Reporter: Steve Loughran
> Assignee: Steve Loughran
> Priority: Minor
> Attachments: HADOOP-8232.patch
>
>
> Add a new command line entry point "topo" with commands for preflight
> checking of a clusters topology setup.
> The initial operations would be to list the implementation class of the
> mapper, and attempt to load it, resolve a set of supplied hostnames, then
> dump the topology map after the resolution process.
> Target audience:
> # ops teams trying to get a new/changed script working before deploying it on
> a cluster.
> # someone trying to write their first script.
> Resolve and list the rack mappings of the given host
> {code}
> hadoop topo test [host1] [host2] ...
> {code}
> This would load the hostnames from a given file, resolve all of them and list
> the results:
> {code}
> hadoop topo testfile filename
> {code}
> This version is intended for the ops team who have a list of hostnames, IP
> addresses.
> * Rather than just list them, the ops team may want to mandate that there
> were no /default-rack mappings found, as that is invariably a sign that the
> script isn't handling a hostname properly.
> * No attempt to be clever and do IP address resolution, FQDN to hostname
> mapping, etc.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
