Hello!
I'm trying to perform a read test of HDFS files through libhdfs using
the hadoop-0.18.2/src/c++/libhdfs/hdfs_read.c test program. Creating
the files succeeds but reading them fails.
I create two 1MB local files with hdfs_write.c and then I put it under hdfs
using hadoop fs -put. The files go under dfs.data.dir as:
hdfs://server:port/dfs.data.dir/file1 and
hdfs://server:port/dfs.data.dir/file2
Then I try to read it back with hdfs_read and measure the time it takes but I
get the following exceptions:
Reading file:///////home/sony/hadoop/dfs/blocks/file1 1MB
Exception in thread "main" java.lang.IllegalArgumentException: Wrong
FS: hdfs://myserver.com:23000/home/sony/hadoop/dfs/blocks/file1,
expected: file:///
at org.apache.hadoop.fs.FileSystem.checkPath(FileSystem.java:320)
at
org.apache.hadoop.fs.RawLocalFileSystem.pathToFile(RawLocalFileSystem.java:52)
Call to
org.apache.hadoop.fs.FileSystem::open((Lorg/apache/hadoop/fs/Path;I)Lorg/apache/hadoop/fs/FSDataInputStream;)
failed!
hdfs_read.c: Failed to open
hdfs://myserver.com:23000/home/sony/hadoop/dfs/blocks/file1 for writing!
..
Reading file:////////home/sony/hadoop/dfs/blocks/file2 1MB
Exception in thread "main" java.lang.IllegalArgumentException: Wrong
FS: hdfs://myserver.com:23000/home/sony/hadoop/dfs/blocks/file2,
expected: file:///
at org.apache.hadoop.fs.FileSystem.checkPath(FileSystem.java:320)
at
org.apache.hadoop.fs.RawLocalFileSystem.pathToFile(RawLocalFileSystem.java:52)
Call to
org.apache.hadoop.fs.FileSystem::open((Lorg/apache/hadoop/fs/Path;I)Lorg/apache/hadoop/fs/FSDataInputStream;)
failed!
hdfs_read.c: Failed to open
hdfs://myserver.com:23000/home/sony/hadoop/dfs/blocks/file2 for writing!
Do I use an incorrect URI? What can be the problem?
Cheers,
Tamas
