Solr: changing the data directory in Windows

Question

I'm trying to change my Solr core's data directly away from the default 'data' directory under the instance directory. I'm using an absolute path because my Solr core's instance and conf directories are buried elsewhere (inside my GitHub directory). I thought it would be as easy as specifying this in core.properties:

dataDir=C:\foo\bar\my_new_data_directory

Inside the 'my_new_data_directory' directory are the following Solr directories:

- index
- tlog

I'm using Windows and am getting the following error when starting up Solr:

ERROR - 2014-01-17 12:40:34.578; org.apache.solr.core.CoreContainer; Unable to create core: collection1
org.apache.solr.common.SolrException
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:680)
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:625)
    at org.apache.solr.core.CoreContainer.createFromLocal(CoreContainer.java:557)
    at org.apache.solr.core.CoreContainer.create(CoreContainer.java:592)
    at org.apache.solr.core.CoreContainer$1.call(CoreContainer.java:271)
    at org.apache.solr.core.CoreContainer$1.call(CoreContainer.java:263)
    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: The filename, directory name, or volume label syntax is incorrect
    at java.io.WinNTFileSystem.canonicalize0(Native Method)
    at java.io.Win32FileSystem.canonicalize(Unknown Source)
    at java.io.File.getCanonicalPath(Unknown Source)
    at org.apache.solr.core.StandardDirectoryFactory.normalize(StandardDirectoryFactory.java:47)
    at org.apache.solr.core.DirectoryFactory.getDataHome(DirectoryFactory.java:246)
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:677)
    ... 13 more

It looks like I'm not specifying the file path properly. How is it supposed to be specified?

Answer 1

I stopped using core.properties a couple of versions ago as variable substitution was not working properly, but I can do this in sorl.xml:

    <core name="core0" instanceDir="core0" dataDir="c:\temp\data" />

and the index path gets properly picked up.

Answer 2

This isn't the most elegant, but the only way I could get this to work properly was to hard code the full path into solrconfig.xml like this:

<dataDir>C:/foo/bar/my_new_data_directory/core1</dataDir>

UPDATE (2014-02-14)

I've realized that I can combine a couple of approaches to get the desired result.

When starting up Solr, I can include this parameter:

data.dir=C:/foo/bar/my_new_data_directory/

Then in solrconfig.xml, I can prefix my data directory with the parameter set during startup:

<dataDir>${solr.data.dir:}core1</dataDir>

This will set the data directory to: C:/foo/bar/my_new_data_directory/core1

With this technique, I can support multiple cores without having the hard code the full path in solrconfig.xml:

C:/foo/bar/my_new_data_directory/core1
C:/foo/bar/my_new_data_directory/core2