当我重新启动Solr时，它将引发以下错误。在hdfs中索引为pdf的Solr集合在solr重新启动期间引发错误。
java.util.concurrent.ExecutionException: org.apache.solr.common.SolrException: Unable to create core [PDFIndex]
at java.util.concurrent.FutureTask.report(FutureTask.java:122)
at java.util.concurrent.FutureTask.get(FutureTask.java:192)
at org.apache.solr.core.CoreContainer.lambda$load$6(CoreContainer.java:594)
at com.codahale.metrics.InstrumentedExecutorService$InstrumentedRunnable.run(InstrumentedExecutorService.java:176)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor.lambda$execute$0(ExecutorUtil.java:229)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.solr.common.SolrException: Unable to create core [PDFIndex]
at org.apache.solr.core.CoreContainer.createFromDescriptor(CoreContainer.java:966)
at org.apache.solr.core.CoreContainer.lambda$load$5(CoreContainer.java:565)
at com.codahale.metrics.InstrumentedExecutorService$InstrumentedCallable.call(InstrumentedExecutorService.java:197)
... 5 more
Caused by: org.apache.solr.common.SolrException: Index dir 'hdfs://192.168.1.16:8020/PDFIndex/data/index/' of core 'PDFIndex' is already locked. The most likely cause is another Solr server (or another solr core in this server) also configured to use this directory; other possible causes may be specific to lockType: hdfs
at org.apache.solr.core.SolrCore.<init>(SolrCore.java:977)
at org.apache.solr.core.SolrCore.<init>(SolrCore.java:830)
at org.apache.solr.core.CoreContainer.createFromDescriptor(CoreContainer.java:950)
... 7 more
Caused by: org.apache.lucene.store.LockObtainFailedException: Index dir 'hdfs://192.168.1.16:8020/PDFIndex/data/index/' of core 'PDFIndex' is already locked. The most likely cause is another Solr server (or another solr core in this server) also configured to use this directory; other possible causes may be specific to lockType: hdfs
at org.apache.solr.core.SolrCore.initIndex(SolrCore.java:712)
at org.apache.solr.core.SolrCore.<init>(SolrCore.java:923)
... 9 more
2018-12-22 07:55:13.431 ERROR (OldIndexDirectoryCleanupThreadForCore-PDFIndex) [ x:PDFIndex] o.a.s.c.HdfsDirectoryFactory Error checking for old index directories to clean-up.
java.io.IOException: Filesystem closed
at org.apache.hadoop.hdfs.DFSClient.checkOpen(DFSClient.java:808)
at org.apache.hadoop.hdfs.DFSClient.listPaths(DFSClient.java:2083)
at org.apache.hadoop.hdfs.DFSClient.listPaths(DFSClient.java:2069)
at org.apache.hadoop.hdfs.DistributedFileSystem.listStatusInternal(DistributedFileSystem.java:791)
at org.apache.hadoop.hdfs.DistributedFileSystem.access$700(DistributedFileSystem.java:106)
at org.apache.hadoop.hdfs.DistributedFileSystem$18.doCall(DistributedFileSystem.java:853)
at org.apache.hadoop.hdfs.DistributedFileSystem$18.doCall(DistributedFileSystem.java:849)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.listStatus(DistributedFileSystem.java:860)
at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:1517)
at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:1557)
at org.apache.solr.core.HdfsDirectoryFactory.cleanupOldIndexDirectories(HdfsDirectoryFactory.java:546)
at org.apache.solr.core.SolrCore.lambda$cleanupOldIndexDirectories$19(SolrCore.java:3050)
at java.lang.Thread.run(Thread.java:748)
2018-12-22 07:55:13.433 ERROR (OldIndexDirectoryCleanupThreadForCore-PDFIndex) [ x:PDFIndex] o.a.s.c.SolrCore Failed to cleanup old index directories for core PDFIndex
java.lang.NullPointerException
at org.apache.solr.core.HdfsDirectoryFactory.cleanupOldIndexDirectories(HdfsDirectoryFactory.java:564)
at org.apache.solr.core.SolrCore.lambda$cleanupOldIndexDirectories$19(SolrCore.java:3050)
at java.lang.Thread.run(Thread.java:748)
我已经在Solr中创建了一个集合，该集合将为pdf文件编制索引，并且该集合正在为HDFS中的所有pdf编制索引。