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1. 背景
做kylin on druid 执行到
报错，错误如下
cube: druid_cube, segment: c96d5afd-dc13-8eb1-a6b6-ecd52b7b9a6d
LoadDruidSegmentStep failed File does not exist: /druid/segments/druid_cube_0/c96d5afd-dc13-8eb1-a6b6-ecd52b7b9a6d/0-descriptor
at org.apache.hadoop.hdfs.server.namenode.INodeFile.valueOf(INodeFile.java:66)
at org.apache.hadoop.hdfs.server.namenode.INodeFile.valueOf(INodeFile.java:56)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getBlockLocationsInt(FSNamesystem.java:2157)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getBlockLocations(FSNamesystem.java:2127)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getBlockLocations(FSNamesystem.java:2040)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.getBlockLocations(NameNodeRpcServer.java:583)
at org.apache.hadoop.hdfs.server.namenode.AuthorizationProviderProxyClientProtocol.getBlockLocations(AuthorizationProviderProxyClientProtocol.java:94)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.getBlockLocations(ClientNamenodeProtocolServerSideTranslatorPB.java:377)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:617)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1073)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2281)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2277)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1924)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2275)
查看文件真的没有这个文件
$ hdfs dfs -ls /druid/segments/druid_cube_0/c96d5afd-dc13-8eb1-a6b6-ecd52b7b9a6d
Found 2 items
-rw-r--r-- 2 deploy supergroup 0 2019-05-09 17:51 /druid/segments/druid_cube_0/c96d5afd-dc13-8eb1-a6b6-ecd52b7b9a6d/_SUCCESS
-rw-r--r-- 2 deploy supergroup 8 2019-05-09 17:51 /druid/segments/druid_cube_0/c96d5afd-dc13-8eb1-a6b6-ecd52b7b9a6d/part-r-00000.deflate
这个原因是因为你选择的CUBE时间范围内恰好没有数据。
选择有数据的范围，生成的CUBE有数据就好了。
然后你可能会遇到下面这个问题
https://blog.csdn.net/qq_21383435/article/details/90047768