[HDFS-10775] Under-Replicated Blocks can not be recovered

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.0.0-alpha1
• Component/s: erasure-coding

Environment

2 NameNodes, 5 DataNodes, Erasured code policy is set as "RS-DEFAULT-3-2-64k"

• Assignee: Aihua Xu
• Reporter: Eisuke Umeda
• Created: 18/Aug/16 08:17
• Updated: 07/Jan/19 19:30

Description

I killed DataNode in the middle of the writing of the EC file. Under-Replicated Blocks has occurred, but did not recover.

DataNodes: datanode[1-5]
Rack awareness: not set
Copy target files: /tmp/tpcds-generate/25/store_sales/*

$ hdfs dfs -ls /tmp/tpcds-generate/25/store_sales
Found 25 items
-rw-r--r--   0 root supergroup  399430918 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00000
-rw-r--r--   0 root supergroup  399054598 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00001
-rw-r--r--   0 root supergroup  399329373 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00002
-rw-r--r--   0 root supergroup  399528459 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00003
-rw-r--r--   0 root supergroup  399329624 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00004
-rw-r--r--   0 root supergroup  399085924 2016-08-16 15:11 /tmp/tpcds-generate/25/store_sales/data-m-00005
-rw-r--r--   0 root supergroup  399337384 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00006
-rw-r--r--   0 root supergroup  399199458 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00007
-rw-r--r--   0 root supergroup  399679096 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00008
-rw-r--r--   0 root supergroup  399440431 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00009
-rw-r--r--   0 root supergroup  399403931 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00010
-rw-r--r--   0 root supergroup  399472465 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00011
-rw-r--r--   0 root supergroup  399451784 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00012
-rw-r--r--   0 root supergroup  399240168 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00013
-rw-r--r--   0 root supergroup  399370507 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00014
-rw-r--r--   0 root supergroup  399633351 2016-08-16 15:12 /tmp/tpcds-generate/25/store_sales/data-m-00015
-rw-r--r--   0 root supergroup  396532952 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00016
-rw-r--r--   0 root supergroup  396258715 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00017
-rw-r--r--   0 root supergroup  396382486 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00018
-rw-r--r--   0 root supergroup  399016456 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00019
-rw-r--r--   0 root supergroup  399465745 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00020
-rw-r--r--   0 root supergroup  399208235 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00021
-rw-r--r--   0 root supergroup  399198296 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00022
-rw-r--r--   0 root supergroup  399599711 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00023
-rw-r--r--   0 root supergroup  395150855 2016-08-16 15:13 /tmp/tpcds-generate/25/store_sales/data-m-00024

Destination directory: /tmp/tpcds-generate/test

$ sudo -u hdfs hdfs erasurecode -getPolicy /tmp/tpcds-generate/test
ErasureCodingPolicy=[Name=RS-DEFAULT-3-2-64k, Schema=[ECSchema=[Codec=rs-default, numDataUnits=3, numParityUnits=2]], CellSize=65536 ]

The following is the steps to reproduce:
1) hdfs dfs -cp /tmp/tpcds-generate/25/store_sales/* /tmp/tpcds-generate/test
2) datanode1: (in the middle of the copy) sudo pkill -9 -f datanode
3) start a process of datanode1 two minutes later
4) wait for a while

Issue Links

• relates to: HDFS-10858 FBR processing may generate incorrect reportedBlock-blockGroup mapping
• relates to: HDFS-10815 The state of the EC file is erroneously recognized when you restart the NameNode.