[ https://issues.apache.org/jira/browse/HDFS-7134?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
gurmukh singh updated HDFS-7134: -------------------------------- Labels: HDFS (was: ) > Replication count for a block should not update till the blocks have settled > on Datanodes > ----------------------------------------------------------------------------------------- > > Key: HDFS-7134 > URL: https://issues.apache.org/jira/browse/HDFS-7134 > Project: Hadoop HDFS > Issue Type: Bug > Components: hdfs > Affects Versions: 1.2.1, 2.6.0, 2.7.3 > Environment: Linux nn1.cluster1.com 2.6.32-431.20.3.el6.x86_64 #1 SMP > Thu Jun 19 21:14:45 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux > [hadoop@nn1 conf]$ cat /etc/redhat-release > CentOS release 6.5 (Final) > Reporter: gurmukh singh > Priority: Critical > Labels: HDFS > > The count for the number of replica's for a block should not change till the > blocks have settled on the datanodes. > Test Case: > Hadoop Cluster with 1 namenode and 3 datanodes. > nn1.cluster1.com(192.168.1.70) > dn1.cluster1.com(192.168.1.72) > dn2.cluster1.com(192.168.1.73) > dn3.cluster1.com(192.168.1.74) > Cluster up and running fine with replication set to "1" for parameter > "dfs.replication on all nodes" > <property> > <name>dfs.replication</name> > <value>1</value> > </property> > To reduce the wait time, have reduced the dfs.heartbeat and recheck > parameters. > on datanode2 (192.168.1.72) > [hadoop@dn2 ~]$ hadoop fs -Ddfs.replication=2 -put from_dn2 / > [hadoop@dn2 ~]$ hadoop fs -ls /from_dn2 > Found 1 items > -rw-r--r-- 2 hadoop supergroup 17 2014-09-23 13:33 /from_dn2 > On Namenode > =========== > As expected, copy was done from datanode2, one copy will go locally. > [hadoop@nn1 conf]$ hadoop fsck /from_dn2 -files -blocks -locations > FSCK started by hadoop from /192.168.1.70 for path /from_dn2 at Tue Sep 23 > 13:53:16 IST 2014 > /from_dn2 17 bytes, 1 block(s): OK > 0. blk_8132629811771280764_1175 len=17 repl=2 [192.168.1.74:50010, > 192.168.1.73:50010] > Can see the blocks on the data nodes disks as well under the "current" > directory. > Now, shutdown datanode2(192.168.1.73) and as expected block moves to another > datanode to maintain a replication of 2 > [hadoop@nn1 conf]$ hadoop fsck /from_dn2 -files -blocks -locations > FSCK started by hadoop from /192.168.1.70 for path /from_dn2 at Tue Sep 23 > 13:54:21 IST 2014 > /from_dn2 17 bytes, 1 block(s): OK > 0. blk_8132629811771280764_1175 len=17 repl=2 [192.168.1.74:50010, > 192.168.1.72:50010] > But, now if i bring back the datanode2, and although the namenode see that > this block is at 3 places now and fires a invalidate command for > datanode1(192.168.1.72) but the replication on the namenode is bumped to 3 > immediately. > [hadoop@nn1 conf]$ hadoop fsck /from_dn2 -files -blocks -locations > FSCK started by hadoop from /192.168.1.70 for path /from_dn2 at Tue Sep 23 > 13:56:12 IST 2014 > /from_dn2 17 bytes, 1 block(s): OK > 0. blk_8132629811771280764_1175 len=17 repl=3 [192.168.1.74:50010, > 192.168.1.72:50010, 192.168.1.73:50010] > on Datanode1 - The invalidate command has been fired immediately and the > block deleted. > ============= > 2014-09-23 13:54:17,483 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Receiving blk_8132629811771280764_1175 src: /192.168.1.74:38099 dest: > /192.168.1.72:50010 > 2014-09-23 13:54:17,502 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Received blk_8132629811771280764_1175 src: /192.168.1.74:38099 dest: > /192.168.1.72:50010 size 17 > 2014-09-23 13:55:28,720 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Scheduling blk_8132629811771280764_1175 file > /space/disk1/current/blk_8132629811771280764 for deletion > 2014-09-23 13:55:28,721 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Deleted blk_8132629811771280764_1175 at file > /space/disk1/current/blk_8132629811771280764 > The namenode still shows 3 replica's. even if one has been deleted, even > after more then 30 mins. > [hadoop@nn1 conf]$ hadoop fsck /from_dn2 -files -blocks -locations > FSCK started by hadoop from /192.168.1.70 for path /from_dn2 at Tue Sep 23 > 14:21:27 IST 2014 > /from_dn2 17 bytes, 1 block(s): OK > 0. blk_8132629811771280764_1175 len=17 repl=3 [192.168.1.74:50010, > 192.168.1.72:50010, 192.168.1.73:50010] > This could be a dangerous, if someone remove or other 2 datanodes fail. > On Datanode 1 > ============= > Before, the datanode1 is brought back > [hadoop@dn1 conf]$ ls -l /space/disk*/current > /space/disk1/current: > total 28 > -rw-rw-r-- 1 hadoop hadoop 13 Sep 21 09:09 blk_2278001646987517832 > -rw-rw-r-- 1 hadoop hadoop 11 Sep 21 09:09 blk_2278001646987517832_1171.meta > -rw-rw-r-- 1 hadoop hadoop 17 Sep 23 13:54 blk_8132629811771280764 > -rw-rw-r-- 1 hadoop hadoop 11 Sep 23 13:54 blk_8132629811771280764_1175.meta > -rw-rw-r-- 1 hadoop hadoop 5299 Sep 21 10:04 dncp_block_verification.log.curr > -rw-rw-r-- 1 hadoop hadoop 157 Sep 23 13:51 VERSION > After, starting datanode daemon > [hadoop@dn1 conf]$ ls -l /space/disk*/current > /space/disk1/current: > total 20 > -rw-rw-r-- 1 hadoop hadoop 13 Sep 21 09:09 blk_2278001646987517832 > -rw-rw-r-- 1 hadoop hadoop 11 Sep 21 09:09 blk_2278001646987517832_1171.meta > -rw-rw-r-- 1 hadoop hadoop 5299 Sep 21 10:04 dncp_block_verification.log.curr > -rw-rw-r-- 1 hadoop hadoop 157 Sep 23 13:51 VERSION > As expected the block is deleted as seen in the logs as well, but namenode > does not update it. > rc: /192.168.1.74:38099 dest: /192.168.1.72:50010 size 17 > 2014-09-23 13:55:28,720 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Scheduling blk_8132629811771280764_1175 file > /space/disk1/current/blk_8132629811771280764 for deletion > 2014-09-23 13:55:28,721 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: > Deleted blk_8132629811771280764_1175 at file > /space/disk1/current/blk_8132629811771280764 > Thanks -- This message was sent by Atlassian JIRA (v6.3.15#6346) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org