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HDFS Balancer exits without balancing

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HDFS Balancer exits without balancing

Contributor

Command ran through shell script:

....Logging
sudo -u hdfs -b hdfs balancer -threshold 5
....

Log: The Balance exits successfully without balancing.

17/05/26 16:38:51 INFO balancer.Balancer: Using a threshold of 5.0
17/05/26 16:38:51 INFO balancer.Balancer: namenodes  = [hdfs://belongcluster1]
17/05/26 16:38:51 INFO balancer.Balancer: parameters = Balancer.BalancerParameters [BalancingPolicy.Node, threshold = 5.0, max idle iteration = 5, #excluded nodes = 0, #included nodes = 0, #source nodes = 0, #blockpools = 0, run during upgrade = false]
17/05/26 16:38:51 INFO balancer.Balancer: included nodes = []
17/05/26 16:38:51 INFO balancer.Balancer: excluded nodes = []
17/05/26 16:38:51 INFO balancer.Balancer: source nodes = []
Time Stamp               Iteration#  Bytes Already Moved  Bytes Left To Move  Bytes Being Moved
17/05/26 16:38:53 INFO balancer.KeyManager: Block token params received from NN: update interval=10hrs, 0sec, token lifetime=10hrs, 0sec
17/05/26 16:38:53 INFO block.BlockTokenSecretManager: Setting block keys
17/05/26 16:38:53 INFO balancer.KeyManager: Update block keys every 2hrs, 30mins, 0sec
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.movedWinWidth = 5400000 (default=5400000)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.moverThreads = 1000 (default=1000)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.dispatcherThreads = 200 (default=200)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.datanode.balance.max.concurrent.moves = 5 (default=5)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.getBlocks.size = 2147483648 (default=2147483648)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.getBlocks.min-block-size = 10485760 (default=10485760)
17/05/26 16:38:53 INFO block.BlockTokenSecretManager: Setting block keys
17/05/26 16:38:53 INFO balancer.Balancer: dfs.balancer.max-size-to-move = 10737418240 (default=10737418240)
17/05/26 16:38:53 INFO balancer.Balancer: dfs.blocksize = 134217728 (default=134217728)
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.144.YYY:50010
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.144.YYY:50010
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.145.YY:50010
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.145.YY:50010
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.145.YY:50010
17/05/26 16:38:53 INFO net.NetworkTopology: Adding a new node: /default-rack/58.XXX.144.YY:50010
17/05/26 16:38:53 INFO balancer.Balancer: 0 over-utilized: []
17/05/26 16:38:53 INFO balancer.Balancer: 0 underutilized: []
The cluster is balanced. Exiting...
May 26, 2017 4:38:53 PM           0                  0 B                 0 B               -1 B
May 26, 2017 4:38:54 PM  Balancing took 2.773 seconds

The Ambari Host view indicates that the data is still not balanced across the nodes:

hostviewambari.jpg

( Updated) The cluster has HA configuration (Primary-Secondary).

Ambari : 2.2.1.0

Hadoop : 2.7.1.2.4.0.0-169

Any input will be helpfull.

12 REPLIES 12

Re: HDFS Balancer exits without balancing

Super Guru
@Suhel
  1. sudo -u hdfs -b hdfs balancer -threshold 5

What do you have "-b" for in this command? Shouldn't this be

sudo -u hdfs hdfs balancer -threshold 5

Re: HDFS Balancer exits without balancing

Contributor

@mqureshi I used "-b" option to push the processing to background. I have also tried the following from server that has NN. Trial 1: (on Command Prompt)

nohup sudo -u hdfs hdfs balancer -threshold 5 > /var/log/hadoop/hdfs/balancer.$(date +%F_%H-%M-%S.%N).log 2>&1 &
Trial 2: (on Command Prompt) . DH05 needs to be offloaded as its the most unbalanced
sudo -u hdfs -b hdfs balancer -threshold 5 -source DH05 > /var/log/hadoop/hdfs/balancer.$(date +%F_%H-%M-%S.%N).log 2>&1 &

I get the same output from Balancer as it exists stating that "The cluster is balanced". It's somehow not able to get the current stats on data in the datanodes.

Re: HDFS Balancer exits without balancing

Super Guru

@Suhel

Do you also have a standby namenode? Can you try the following:

sudo -u hdfs -b hdfs balancer -fs hdfs://<your name node>:8020 -threshold 5

Re: HDFS Balancer exits without balancing

Contributor

@mqureshi The cluster has a primary and secondary configuration for NN. When i run the balance command as you indicated, i get an error stating "Another Balancer is running". But ps -ef | grep balancer does not show any running balancer process

[root@dh01 ~]# sudo -u hdfs hdfs balancer -fs hdfs://dh01.int.belong.com.au:8020 -threshold 5
17/05/29 12:14:53 INFO balancer.Balancer: Using a threshold of 5.0
17/05/29 12:14:53 INFO balancer.Balancer: namenodes  = [hdfs://belongcluster1, hdfs://dh01.int.belong.com.au:8020]
17/05/29 12:14:53 INFO balancer.Balancer: parameters = Balancer.BalancerParameters [BalancingPolicy.Node, threshold = 5.0, max idle iteration = 5, #excluded nodes = 0, #included nodes = 0, #source nodes = 0, #blockpools = 0, run during upgrade = false]
17/05/29 12:14:53 INFO balancer.Balancer: included nodes = []
17/05/29 12:14:53 INFO balancer.Balancer: excluded nodes = []
17/05/29 12:14:53 INFO balancer.Balancer: source nodes = []
Time Stamp               Iteration#  Bytes Already Moved  Bytes Left To Move  Bytes Being Moved
17/05/29 12:14:54 INFO balancer.KeyManager: Block token params received from NN: update interval=10hrs, 0sec, token lifetime=10hrs, 0sec
17/05/29 12:14:54 INFO block.BlockTokenSecretManager: Setting block keys
17/05/29 12:14:54 INFO balancer.KeyManager: Update block keys every 2hrs, 30mins, 0sec
17/05/29 12:14:55 INFO block.BlockTokenSecretManager: Setting block keys
17/05/29 12:14:55 INFO balancer.KeyManager: Block token params received from NN: update interval=10hrs, 0sec, token lifetime=10hrs, 0sec
17/05/29 12:14:55 INFO block.BlockTokenSecretManager: Setting block keys
17/05/29 12:14:55 INFO balancer.KeyManager: Update block keys every 2hrs, 30mins, 0sec
java.io.IOException: Another Balancer is running..  Exiting ...
May 29, 2017 12:14:55 PM Balancing took 2.431 seconds


Re: HDFS Balancer exits without balancing

Super Guru

Re: HDFS Balancer exits without balancing

Contributor

@mqureshi

About : https://community.hortonworks.com/articles/4595/balancer-not-working-in-hdfs-ha.html

my hdfs-site.xml has 2 entries .. i am not sure if i need to delete both or NN2 only..

    <property>
      <name>dfs.namenode.rpc-address.belongcluster1.nn1</name>
      <value>dh01.int.belong.com.au:8020</value>
    </property>
    
    <property>
      <name>dfs.namenode.rpc-address.belongcluster1.nn2</name>
      <value>dh02.int.belong.com.au:8020</value>
    </property>

Re: HDFS Balancer exits without balancing

Super Guru

@Suhel

I think you should have only one value and it should point to your "name service". You should have a value for name service when you have HA enabled. See the following link on how this works in HA - third row:

https://hadoop.apache.org/docs/r2.4.1/hadoop-project-dist/hadoop-hdfs/hdfs-default.xml

Re: HDFS Balancer exits without balancing

Contributor

@mqureshi I found another thread with similar issue: https://community.hortonworks.com/questions/22105/hdfs-balancer-is-getting-failed-after-30-mins-in-a... here they say indicate that if HA is enabled then one would need to remove dfs.namenode.rpc-address . I ran a check on Ambari Server using the configs.sh:

/var/lib/ambari-server/resources/scripts/configs.sh -u admin -p admin -port 8080 get dh01.int.belong.com.au belong1 hdfs-site

and the output does not contain the dfs.namenode.rpc-address property.

########## Performing 'GET' on (Site:hdfs-site, Tag:version1470359698835)
"properties" : {
"dfs.block.access.token.enable" : "true",
"dfs.blockreport.initialDelay" : "120",
"dfs.blocksize" : "134217728",
"dfs.client.block.write.replace-datanode-on-failure.enable" : "NEVER",
"dfs.client.failover.proxy.provider.belongcluster1" : "org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider",
"dfs.client.read.shortcircuit" : "true",
"dfs.client.read.shortcircuit.streams.cache.size" : "4096",
"dfs.client.retry.policy.enabled" : "false",
"dfs.cluster.administrators" : " hdfs",
"dfs.content-summary.limit" : "5000",
"dfs.datanode.address" : "0.0.0.0:50010",
"dfs.datanode.balance.bandwidthPerSec" : "6250000",
"dfs.datanode.data.dir" : "/data/hadoop/hdfs/data",
"dfs.datanode.data.dir.perm" : "750",
"dfs.datanode.du.reserved" : "1073741824",
"dfs.datanode.failed.volumes.tolerated" : "0",
"dfs.datanode.http.address" : "0.0.0.0:50075",
"dfs.datanode.https.address" : "0.0.0.0:50475",
"dfs.datanode.ipc.address" : "0.0.0.0:8010",
"dfs.datanode.max.transfer.threads" : "16384",
"dfs.domain.socket.path" : "/var/lib/hadoop-hdfs/dn_socket",
"dfs.encrypt.data.transfer.cipher.suites" : "AES/CTR/NoPadding",
"dfs.encryption.key.provider.uri" : "",
"dfs.ha.automatic-failover.enabled" : "true",
"dfs.ha.fencing.methods" : "shell(/bin/true)",
"dfs.ha.namenodes.belongcluster1" : "nn1,nn2",
"dfs.heartbeat.interval" : "3",
"dfs.hosts.exclude" : "/etc/hadoop/conf/dfs.exclude",
"dfs.http.policy" : "HTTP_ONLY",
"dfs.https.port" : "50470",
"dfs.journalnode.edits.dir" : "/hadoop/hdfs/journal",
"dfs.journalnode.https-address" : "0.0.0.0:8481",
"dfs.namenode.accesstime.precision" : "0",
"dfs.namenode.acls.enabled" : "true",
"dfs.namenode.audit.log.async" : "true",
"dfs.namenode.avoid.read.stale.datanode" : "true",
"dfs.namenode.avoid.write.stale.datanode" : "true",
"dfs.namenode.checkpoint.dir" : "/tmp/hadoop/hdfs/namesecondary",
"dfs.namenode.checkpoint.edits.dir" : "${dfs.namenode.checkpoint.dir}",
"dfs.namenode.checkpoint.period" : "21600",
"dfs.namenode.checkpoint.txns" : "1000000",
"dfs.namenode.fslock.fair" : "false",
"dfs.namenode.handler.count" : "200",
"dfs.namenode.http-address" : "dh01.int.belong.com.au:50070",
"dfs.namenode.http-address.belongcluster1.nn1" : "dh01.int.belong.com.au:50070",
"dfs.namenode.http-address.belongcluster1.nn2" : "dh02.int.belong.com.au:50070",
"dfs.namenode.https-address" : "dh01.int.belong.com.au:50470",
"dfs.namenode.https-address.belongcluster1.nn1" : "dh01.int.belong.com.au:50470",
"dfs.namenode.https-address.belongcluster1.nn2" : "dh02.int.belong.com.au:50470",
"dfs.namenode.name.dir" : "/data/hadoop/hdfs/namenode",
"dfs.namenode.name.dir.restore" : "true",
"dfs.namenode.rpc-address.belongcluster1.nn1" : "dh01.int.belong.com.au:8020",
"dfs.namenode.rpc-address.belongcluster1.nn2" : "dh02.int.belong.com.au:8020",
"dfs.namenode.safemode.threshold-pct" : "0.99",
"dfs.namenode.shared.edits.dir" : "qjournal://dh03.int.belong.com.au:8485;dh02.int.belong.com.au:8485;dh01.int.belong.com.au:8485/belongcluster1",
"dfs.namenode.stale.datanode.interval" : "30000",
"dfs.namenode.startup.delay.block.deletion.sec" : "3600",
"dfs.namenode.write.stale.datanode.ratio" : "1.0f",
"dfs.nameservices" : "belongcluster1",
"dfs.permissions.enabled" : "true",
"dfs.permissions.superusergroup" : "hdfs",
"dfs.replication" : "3",
"dfs.replication.max" : "50",
"dfs.support.append" : "true",
"dfs.webhdfs.enabled" : "true",
"fs.permissions.umask-mode" : "022",
"nfs.exports.allowed.hosts" : "* rw",
"nfs.file.dump.dir" : "/tmp/.hdfs-nfs"
}

Are you suggesting that i just keep 1 namenode service address and point it to primary name node host:port. Something like the below:

    <property>
      <name>dfs.namenode.rpc-address.belongcluster1</name>
      <value>dh01.int.belong.com.au:8020</value>
    </property>

Re: HDFS Balancer exits without balancing

Super Guru
@Suhel

Actually, don't delete anything. Your version of Ambari does not seem to be affected by this bug. Try the following:

sudo -u hdfs -b hdfs balancer -fs hdfs://belongcluster1:8020 -threshold 5

My guess is you were only missing port number. Can you please try it.