hadoop - 如何检查hdfs上的分布式数据

Question

我们知道，Hadoop将数据复制到hdfs中的多个数据节点上，有没有命令可以查看分布在不同节点上的数据。

Answer 1

我想你可能正在寻找这个命令

hdfs fsck /hdfs/path/to/data -files -blocks -locations

您会收到如下所示的报告。它报告所有 block 的列表、它们的复制因子以及 block 所在的主机集。

/hdfs/path/to/data/file.txt 4771082824 bytes, 36 block(s):  OK
0. BP-22525430-10.14.103.78-1355873316066:blk_-3400885615428218530_203522 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
1. BP-22525430-10.14.103.78-1355873316066:blk_124203196739652236_203523 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
2. BP-22525430-10.14.103.78-1355873316066:blk_5886188080028552249_203524 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
3. BP-22525430-10.14.103.78-1355873316066:blk_-3222807870390148132_203525 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
4. BP-22525430-10.14.103.78-1355873316066:blk_-1285830390698132620_203526 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
5. BP-22525430-10.14.103.78-1355873316066:blk_-2680874809037637827_203527 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
6. BP-22525430-10.14.103.78-1355873316066:blk_8699277646297360652_203528 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
7. BP-22525430-10.14.103.78-1355873316066:blk_-2195916588803548138_203529 len=134217728 repl=3 [10.14.103.213:50010, 10.14.102.190:50010, 10.14.102.176:50010]
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