在配置后端状态以使用hdfs时出错

时间:2018-12-19 12:35:01

标签: scala hadoop apache-flink

我正在尝试将后端状态设置为hdfs

val stateUri = "hdfs/path_to_dir"
val backend: RocksDBStateBackend = new RocksDBStateBackend(stateUri, true)
env.setStateBackend(backend)

我正在使用具有以下依赖项的flink 1.7.0(我尝试了所有组合):

   "org.apache.flink"    %% "flink-connector-filesystem"         % flinkV
"org.apache.flink"    % "flink-hadoop-fs"                     % flinkV
"org.apache.hadoop"   % "hadoop-hdfs"                         % hadoopVersion
"org.apache.hadoop"   % "hadoop-common"                       % hadoopVersion

但是在运行jar时出现此错误:

Caused by: org.apache.flink.core.fs.UnsupportedFileSystemSchemeException: Could not find a file system implementation for scheme 'hdfs'. The scheme is not directly supported by Flink and no Hadoop file system to support this scheme could be loaded.
    at org.apache.flink.core.fs.FileSystem.getUnguardedFileSystem(FileSystem.java:403)
    at org.apache.flink.core.fs.FileSystem.get(FileSystem.java:318)
    at org.apache.flink.core.fs.Path.getFileSystem(Path.java:298)
    at org.apache.flink.runtime.state.filesystem.FsCheckpointStorage.<init>(FsCheckpointStorage.java:58)
    at org.apache.flink.runtime.state.filesystem.FsStateBackend.createCheckpointStorage(FsStateBackend.java:444)
    at org.apache.flink.contrib.streaming.state.RocksDBStateBackend.createCheckpointStorage(RocksDBStateBackend.java:407)
    at org.apache.flink.runtime.checkpoint.CheckpointCoordinator.<init>(CheckpointCoordinator.java:249)
    ... 17 more
Caused by: org.apache.flink.core.fs.UnsupportedFileSystemSchemeException: Hadoop is not in the classpath/dependencies.
    at org.apache.flink.core.fs.UnsupportedSchemeFactory.create(UnsupportedSchemeFactory.java:64)
    at org.apache.flink.core.fs.FileSystem.getUnguardedFileSystem(FileSystem.java:399)
    ... 23 more

任何帮助将不胜感激

1 个答案:

答案 0 :(得分:0)

要访问hdfs://路径,只要您在Flink安装的flink-hadoop-fs文件夹中有flink-shaded-hadoop2-uber-1.8-SNAPSHOT.jar,就不必严格将lib与您的工作捆绑在一起

如果您的lib文件夹中没有此依赖项,那么我建议使用flink-fs-hadoop-shaded作为依赖项,因为它还会重新放置Hadoop依赖项。

此外,重要的是,此依赖项也应包含在结果作业jar中。因此,请确保使用sbt-assembly插件创建一个uber-jar。